N-CSRS

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D. C. 20549

FORM N-CSRS

Investment Company Act file number: 811-06073

Government Cash Management Portfolio

(Exact Name of Registrant as Specified in Charter)

345 Park Avenue

New York, NY 10154-0004

(Address of Principal Executive Offices) (Zip Code)

Registrant’s Telephone Number, including Area Code: (212) 250-2500

Diane Kenneally

1 International Place

Boston, MA 02110

(Name and Address of Agent for Service)

Date of fiscal year end:	12/31
Date of reporting period:	6/30/2018

ITEM 1. REPORT TO STOCKHOLDERS

Table of Contents

June 30, 2018

Semiannual Report

to Shareholders

DWS Government Cash Management Fund

(formerly Deutsche Government Cash Management Fund)

Table of Contents

Contents

DWS Government Cash Management Fund
3	Portfolio Summary
4	Statement of Assets and Liabilities
5	Statement of Operations
6	Statements of Changes in Net Assets
7	Financial Highlights
8	Notes to Financial Statements
12	Information About Your Fund’s Expenses
Government Cash Management Portfolio
15	Investment Portfolio
20	Statement of Assets and Liabilities
21	Statement of Operations
22	Statements of Changes in Net Assets
23	Financial Highlights
24	Notes to Financial Statements
29	Advisory Agreement Board Considerations and Fee Evaluation
34	Account Management Resources
36	Privacy Statement

This report must be preceded or accompanied by a prospectus. To obtain a summary prospectus, if available, or prospectus for any of our funds, refer to the Account Management Resources information provided in the back of this booklet. We advise you to consider the Fund’s objectives, risks, charges and expenses carefully before investing. The summary prospectus and prospectus contain this and other important information about the Fund. Please read the prospectus carefully before you invest.

You could lose money by investing in the Fund. Although the Fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so. An investment in the Fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The Fund’s sponsor has no legal obligation to provide financial support to the Fund, and you should not expect that the sponsor will provide financial support to the Fund at any time. You should not rely on or expect the Advisor to enter into support agreements or take other actions to maintain the Fund’s $1.00 share price. The credit quality of the Fund’s holdings can change rapidly in certain markets, and the default of a single holding could have an adverse impact on the Fund’s share price. The Fund’s share price can also be negatively affected during periods of high redemption pressures and/or illiquid markets. The actions of a few large investors of the Fund may have a significant adverse effect on the share price of the Fund. Please read the prospectus for specific details regarding the Fund’s risk profile.

The brand DWS represents DWS Group GmbH & Co. KGaA and any of its subsidiaries such as DWS Distributors, Inc. which offers investment products or DWS Investment Management Americas, Inc. and RREEF America L.L.C. which offer advisory services.

NOT FDIC/NCUA INSURED     NO BANK GUARANTEE     MAY LOSE VALUE NOT A DEPOSIT     NOT INSURED BY ANY FEDERAL GOVERNMENT AGENCY

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Portfolio Summary		(Unaudited)
Asset Allocation (As a % of Investment Portfolio)	6/30/18		12/31/17
Government & Agency Obligations		92%		90%
Repurchase Agreements		8%		10%
		100%		100%
Weighted Average Maturity	6/30/18		12/31/17
DWS Government Cash Management Fund		32 days		43 days
Government & Agency Institutional*		29 days		31 days

* The Fund is compared to its respective iMoneyNet category: Government & Agency Institutional — Category includes the most broadly based of the government institutional funds. These funds may invest in U.S. Treasury securities, securities issued or guaranteed by the U.S. Government or its agencies or instrumentalities.

Weighted average maturity, also known as effective maturity, is the weighted average of the maturity date of bonds held by the Fund taking into consideration any available maturity shortening features.

Portfolio holdings and characteristics are subject to change.

For more complete details about the portfolio’s holdings, see page 15. A quarterly Fact Sheet is available on liquidity.dws.com/US/products/fund_facts_prospectus_l2.jsp or upon request. Please see the Account Management Resources section on page 34 for contact information.

DWS Government Cash Management Fund | 3

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Statement of Assets and Liabilities

as of June 30, 2018 (Unaudited)
Assets
Investment in Government Cash Management Portfolio, at value	$	1,763,133,675
Receivable for Fund shares sold		262
Other assets		12,641
Total assets		1,763,146,578
Liabilities
Payable for Fund shares redeemed		18
Distributions payable		224,098
Accrued Trustees’ fees		438
Other accrued expenses and payables		444,184
Total liabilities		668,738
Net assets, at value	$	1,762,477,840
Net Assets Consist of
Distributions in excess of net investment income		(121	)
Accumulated net realized gain (loss)		32,934
Paid-in capital		1,762,445,027
Net assets, at value	$	1,762,477,840
Net Asset Value
Institutional Shares
Net Asset Value, offering and redemption price per share ($1,762,477,840 ÷ 1,762,539,886 outstanding shares of beneficial interest, $.01 par value, unlimited number of shares authorized)	$	1.00

The accompanying notes are an integral part of the financial statements.

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Statement of Operations

for the six months ended June 30, 2018 (Unaudited)
Investment Income
Income and expenses allocated from Government Cash Management Portfolio:
Interest	$	14,672,191
Expenses*		(875,093	)
Net investment income allocated from Government Cash Management Portfolio		13,797,098
Expenses:
Administration fee		890,733
Services to shareholders		35,503
Service fees		548,876
Professional fees		20,557
Reports to shareholders		9,890
Registration fees		11,894
Trustees’ fees and expenses		2,383
Other		19,405
Total expenses		1,539,241
Net investment income		12,257,857
Net realized gain (loss) allocated from Government Cash Management Portfolio		(4,201	)
Net increase (decrease) in net assets resulting from operations	$	12,253,656

* Net of $362,639 Advisor reimbursement allocated from Government Cash Management Portfolio for the six months ended June 30, 2018.

The accompanying notes are an integral part of the financial statements.

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Statements of Changes in Net Assets

	Six Months Ended June 30, 2018 (Unaudited)			Year Ended December 31, 2017
Increase (Decrease) in Net Assets
Operations:
Net investment income	$	12,257,857		$	9,702,081
Net realized gain (loss)		(4,201	)		37,135
Net increase (decrease) in net assets resulting from operations		12,253,656			9,739,216
Distributions to shareholders from:
Net investment income		(12,261,061	)		(9,700,252	)
Fund share transactions:
Proceeds from shares sold		2,218,916,310			3,685,868,695
Reinvestment of distributions		11,329,863			8,780,803
Payments for shares redeemed		(2,150,204,706	)		(4,001,787,613	)
Net increase (decrease) in net assets from Fund share transactions		80,041,467			(307,138,115	)
Increase (decrease) in net assets		80,034,062			(307,099,151	)
Net assets at beginning of period		1,682,443,778			1,989,542,929
Net assets at end of period (including distributions in excess of net investment income and undistributed net investment income of $121 and $3,083, respectively)	$	1,762,477,840		$	1,682,443,778
Other Information:
Shares outstanding at beginning of period		1,682,498,419			1,989,636,534
Shares sold		2,218,916,310			3,685,868,695
Shares issued to shareholders in reinvestment of distributions		11,329,863			8,780,803
Shares redeemed		(2,150,204,706	)		(4,001,787,613	)
Net increase (decrease) in Fund shares		80,041,467			(307,138,115	)
Shares outstanding at end of period		1,762,539,886			1,682,498,419

The accompanying notes are an integral part of the financial statements.

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Financial Highlights

Institutional Shares	Six Months Ended 6/30/18				Years Ended December 31,
	(Unaudited)				2017			2016			2015			2014			2013
Selected Per Share Data
Net asset value, beginning of period		$	1.00		$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Income from investment operations:
Net investment income			.007			.006			.002			.000	***		.000	***		.000	***
Net realized gain (loss)			(.000	)***		.000	***		.000	***		.000	***		.000	***		.000	***
Total from investment operations			.007			.006			.002			.000	***		.000	***		.000	***
Less distributions from:
Net investment income			(.007	)		(.006	)		(.002	)		(.000	)***		(.000	)***		(.000	)***
Net asset value, end of period		$	1.00		$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Total Return (%)a			.67	**		.64			.16			.01			.01			.01
Ratios to Average Net Assets and Supplemental Data
Net assets, end of period ($ millions)			1,762			1,682			1,990			2,202			911			1,536
Ratio of expenses before expense reductions, including expenses allocated from Government Cash Management Portfolio (%)			.31	*		.32			.32			.34			.34			.33
Ratio of expenses after expense reductions, including expenses allocated from Government Cash Management Portfolio (%)			.27	*		.28			.27			.24			.18			.21
Ratio of net investment income (%)			1.38	*		.63			.16			.02			.01			.01

^a Total return would have been lower had certain expenses not been reduced.

^* Annualized

^** Not annualized

^*** Amount is less than $.0005.

The accompanying notes are an integral part of the financial statements.

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Notes to Financial Statements (Unaudited)

A. Organization and Significant Accounting Policies

DWS Government Cash Management Fund (formerly Deutsche Government Cash Management Fund) (the “Fund”) is a diversified series of Deutsche DWS Money Market Trust (formerly Deutsche Money Market Trust) (the “Trust”), which is registered under the Investment Company Act of 1940, as amended (the “1940 Act”), as an open-end management investment company organized as a Massachusetts business trust. The Fund currently offers one class of shares, Institutional Shares, to investors.

The Fund is a feeder fund that seeks to achieve its investment objective by investing substantially all of its investable assets in a master portfolio, the Government Cash Management Portfolio (the “Portfolio”), an open-end management investment company registered under the 1940 Act and organized as a New York trust advised by DWS Investment Management Americas, Inc. (formerly Deutsche Investment Management Americas Inc.) (“DIMA” or the “Advisor”), an indirect, wholly owned subsidiary of DWS Group GmbH & Co. KGaA (“DWS Group”). A master/feeder fund structure is one in which a fund (a “feeder fund”), instead of investing directly in a portfolio of securities, invests most or all of its investment assets in a separate registered investment company (the “master fund”) with substantially the same investment objective and policies as the feeder fund. Such a structure permits the pooling of assets of two or more feeder funds, preserving separate identities or distribution channels at the feeder fund level. At June 30, 2018, the Fund owned approximately 11% of the Portfolio.

The Fund’s financial statements are prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) which require the use of management estimates. Actual results could differ from those estimates. The Fund qualifies as an investment company under Topic 946 of Accounting Standards Codification of U.S. GAAP. The policies described below are followed consistently by the Fund in the preparation of its financial statements. The financial statements of the Portfolio, including the Investment Portfolio, are contained elsewhere in this report and should be read in conjunction with the Fund’s financial statements.

Security Valuation. The Fund records its investment in the Portfolio at value, which reflects its proportionate interest in the net assets of the Portfolio and is categorized as Level 1. Valuation of the securities held by the Portfolio is discussed in the notes to the Portfolio’s financial statements included elsewhere in this report.

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Disclosure about the classification of fair value measurements is included in a table following the Portfolio’s Investment Portfolio.

Federal Income Taxes. The Fund’s policy is to comply with the requirements of the Internal Revenue Code, as amended, which are applicable to regulated investment companies, and to distribute all of its taxable income to its shareholders.

The Fund has reviewed the tax positions for the open tax years as of December 31, 2017 and has determined that no provision for income tax and/or uncertain tax provisions is required in the Fund’s financial statements. The Fund’s federal tax returns for the prior three fiscal years remain open subject to examination by the Internal Revenue Service.

Distribution of Income and Gains. Net investment income of the Fund is declared as a daily dividend and is distributed to shareholders monthly. The Fund may take into account capital gains and losses in its daily dividend declarations. The Fund may also make additional distributions for tax purposes if necessary.

Permanent book and tax differences relating to shareholder distributions will result in reclassifications to paid in capital. Temporary book and tax differences will reverse in a subsequent period. There were no significant book to tax differences for the Fund.

The tax character of current year distributions will be determined at the end of the current fiscal year.

Contingencies. In the normal course of business, the Fund may enter into contracts with service providers that contain general indemnification clauses. The Fund’s maximum exposure under these arrangements is unknown, as this would involve future claims that may be made against the Fund that have not yet been made. However, based on experience, the Fund expects the risk of loss to be remote.

Other. The Fund receives an allocation of the Portfolio’s net investment income and net realized gains and losses in proportion to its investment in the Portfolio. Expenses directly attributed to a fund are charged to that fund, while expenses which are attributable to the Trust are allocated among the funds in the Trust on the basis of relative net assets.

B. Fees and Transactions with Affiliates

Management Agreement. Under the Investment Management Agreement with DWS Investment Management Americas, Inc. (formerly

Deutsche Investment Management Americas Inc.) (“DIMA” or the “Advisor”), an indirect, wholly owned subsidiary of DWS Group GmbH & Co. KGaA (“DWS Group”), the Advisor serves as the investment manager to the Fund. The Advisor receives a management fee from the Portfolio pursuant to the master/feeder structure listed above in Note A.

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For the period from January 1, 2018 through April 30, 2019, DIMA has contractually agreed to waive its fees and/or reimburse certain operating expenses of the Fund, including expenses of the Portfolio allocated to the Fund, to the extent necessary to maintain the total annual operating expenses (excluding certain expenses such as extraordinary expenses, taxes, brokerage and interest) at 0.30% of the Fund’s average daily net assets.

Administration Fee. Pursuant to an Administrative Services Agreement, DIMA provides most administrative services to the Fund. For all services provided under the Administrative Services Agreement, the Fund pays the Advisor an annual fee (“Administration Fee”) of 0.10% of the Fund’s average daily net assets, computed and accrued daily and payable monthly. For the six months ended June 30, 2018, the Administration Fee was $890,733, of which $177,987 is unpaid.

Service Provider Fees. DWS Service Company (“DSC”), an affiliate of the Advisor, is the transfer agent, dividend-paying agent and shareholder service agent for the Fund. Pursuant to a sub-transfer agency agreement between DSC and DST Systems, Inc. (“DST”), DSC has delegated certain transfer agent, dividend-paying agent and shareholder service agent functions to DST. DSC compensates DST out of the shareholder servicing fee it receives from the Fund. For the six months ended June 30, 2018, the amount charged to the Fund by DSC aggregated $33,412, of which $19,530 is unpaid.

Shareholder Servicing Fee. DWS Distributors, Inc. (“DDI”), an affiliate of the Advisor, provides information and administrative services for a fee (“Service Fee”) to shareholders at an annual rate of up to 0.25% of average daily net assets. DDI in turn has various agreements with financial services firms that provide these services and pay these fees based upon the assets of shareholder accounts the firms service. For six

months ended June 30, 2018, the Service Fee was as follows:

	Total Aggregated		Unpaid at June 30, 2018		Annualized Rate
DWS Government Cash Management Fund	$	548,876	$	209,627		.06	%

Typesetting and Filing Service Fees. Under an agreement with DIMA, DIMA is compensated for providing certain pre-press and regulatory filing services to the Fund. For the six months ended June 30, 2018, the amount charged to the Fund by DIMA included in the Statement of Operations under “Reports to shareholders“ aggregated $7,609, all of which is unpaid.

Trustees’ Fees and Expenses. The Fund paid retainer fees to each Trustee not affiliated with the Advisor, plus specified amounts to the Board Chairperson and Vice Chairperson and to each committee Chairperson.

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C. Concentration of Ownership

From time to time, the Fund may have a concentration of several shareholder accounts holding a significant percentage of shares outstanding. Investment activities of these shareholders could have a material impact on the Fund.

At June 30, 2018, there was one shareholder account that held approximately 83% of the outstanding shares of the Fund.

D. Name Changes

In connection with adoption of the DWS brand, effective July 2, 2018, Deutsche Investment Management Americas Inc., the Advisor, was renamed to DWS Investment Management Americas, Inc. In addition, the “Deutsche Funds” became known as the “DWS Funds.” As a result, Deutsche Government Cash Management Fund was renamed DWS Government Cash Management Fund.

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Information About Your Fund’s Expenses

As an investor of the Fund, you incur two types of costs: ongoing expenses and transaction costs. Ongoing expenses include management fees and other Fund expenses. Examples of transaction costs include account maintenance fees, which are not shown in this section. The following tables are intended to help you understand your ongoing expenses (in dollars) of investing in the Fund and to help you compare these expenses with the ongoing expenses of investing in other mutual funds. In the most recent six-month period, the Fund limited these expenses; had it not done so, expenses would have been higher. The example in the table is based on an investment of $1,000 invested at the beginning of the six-month period and held for the entire period (January 1, 2018 to June 30, 2018).

The tables illustrate your Fund’s expenses in two ways:

– Actual Fund Return. This helps you estimate the actual dollar amount of ongoing expenses (but not transaction costs) paid on a $1,000 investment in the Fund using the Fund’s actual return during the period. To estimate the expenses you paid over the period, simply divide your account value by $1,000 (for example, an $8,600 account value divided by $1,000 = 8.6), then multiply the result by the number in the “Expenses Paid per $1,000” line under the share class you hold.

– Hypothetical 5% Fund Return. This helps you to compare your Fund’s ongoing expenses (but not transaction costs) with those of other mutual funds using the Fund’s actual expense ratio and a hypothetical rate of return of 5% per year before expenses. Examples using a 5% hypothetical fund return may be found in the shareholder reports of other mutual funds. The hypothetical account values and expenses may not be used to estimate the actual ending account balance or expenses you paid for the period.

Please note that the expenses shown in these tables are meant to highlight your ongoing expenses only and do not reflect any transaction costs. The “Expenses Paid per $1,000” line of the tables is useful in comparing ongoing expenses only and will not help you determine the relative total expense of owning different funds. If these transaction costs had been included, your costs would have been higher.

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Expenses and Value of a $1,000 Investment for the six months ended June 30, 2018 (Unaudited)
Actual Fund Return*	Institutional Shares
Beginning Account Value 1/1/18	$	1,000.00
Ending Account Value 6/30/18	$	1,006,75
Expenses Paid per $1,000**	$	1.34
Hypothetical 5% Fund Return
Beginning Account Value 1/1/18	$	1,000.00
Ending Account Value 6/30/18	$	1,023.46
Expenses Paid per $1,000**	$	1.35

* Expenses include amounts allocated proportionally from the master portfolio.

** Expenses are equal to the Fund’s annualized expense ratio, multiplied by the average account value over the period, multiplied by 181 (the number of days in the most recent six-month period), then divided by 365.

Annualized Expense Ratio	Institutional Shares
DWS Government Cash Management Fund		.27%

For more information, please refer to the Fund’s prospectus.

For an analysis of the fees associated with an investment in the Fund or similar funds, please refer to http://apps.finra.org/fundanalyzer/1/fa.aspx.

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(The following financial statements of the Government Cash Management Portfolio should be read in conjunction with the Fund’s financial statements.)

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Investment Portfolio as of June 30, 2018 (Unaudited)

Government Cash Management Portfolio

	Principal Amount ($)		Value ($)
Government & Agency Obligations 91.6%
U.S. Government Sponsored Agencies 57.4%
Federal Farm Credit Bank:
1-month LIBOR minus 0.165%, 1.836%*, 11/2/2018		70,500,000		70,499,400
1-month LIBOR minus 0.165%, 1.881%*, 10/9/2018		37,500,000		37,499,454
1-month LIBOR minus 0.150%, 1.896%*, 10/11/2018		25,000,000		24,999,790
1-month LIBOR minus 0.135%, 1.911%*, 4/11/2019		150,000,000		150,000,000
1-month LIBOR minus 0.110%, 1.936%*, 3/12/2019		115,000,000		114,995,656
1-month LIBOR minus 0.145%, 1.949%*, 3/29/2019		166,000,000		166,000,000
1-month LIBOR minus 0.145%, 1.953%*, 2/26/2019		115,000,000		114,996,961
1-month LIBOR minus 0.130%, 1.964%*, 4/29/2019		246,500,000		246,500,000
1-month LIBOR minus 0.120%, 1.971%*, 3/25/2019		100,000,000		100,000,000
1-month LIBOR minus 0.070%, 1.976%*, 1/9/2019		50,000,000		50,000,000
1-month LIBOR minus 0.065%, 2.019%*, 7/20/2018		68,800,000		68,800,000
1-month LIBOR minus 0.003%, 2.133%*, 8/27/2018		75,000,000		74,999,088
3-month U.S. Treasury Bill Money Market Yield plus 0.280%, 2.189%*, 11/13/2018		60,000,000		60,000,000
3-month U.S. Treasury Bill Money Market Yield plus 0.300%, 2.209%*, 12/5/2018		50,000,000		50,000,000
Federal Home Loan Bank:
1.572%**, 7/2/2018		114,799,000		114,794,057
1-month LIBOR minus 0.160%, 1.822%*, 8/1/2018		200,000,000		200,000,000
1.825%**, 7/3/2018		115,500,000		115,488,450
1-month LIBOR minus 0.160%, 1.841%*, 8/3/2018		370,000,000		370,000,000
1.845%**, 7/24/2018		64,000,000		63,925,582
1-month LIBOR minus 0.155%, 1.85%*, 7/5/2018		205,000,000		205,000,000
1.86%**, 7/20/2018		75,000,000		74,927,364
1.86%**, 7/23/2018		75,000,000		74,915,896
1.87%**, 8/24/2018		78,000,000		77,784,252
1.873%**, 8/1/2018		100,000,000		99,840,953
1.88%**, 7/13/2018		286,500,000		286,322,943
1.881%**, 7/23/2018		343,250,000		342,860,888
1.886%**, 7/20/2018		800,000		799,215
1-month LIBOR minus 0.145%, 1.902%*, 8/13/2018		35,000,000		35,000,000
1-month LIBOR minus 0.090%, 1.915%*, 4/5/2019		88,000,000		88,000,000
1-month LIBOR minus 0.080%, 1.921%*, 2/4/2019		95,000,000		95,000,000
1-month LIBOR minus 0.090%, 1.923%*, 4/5/2019		150,000,000		150,000,000
1-month LIBOR minus 0.160%, 1.925%*, 7/19/2018		240,000,000		240,000,000
1-month LIBOR minus 0.130%, 1.927%*, 3/22/2019		233,250,000		233,250,000

The accompanying notes are an integral part of the financial statements.

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	Principal Amount ($)		Value ($)
1-month LIBOR minus 0.145%, 1.928%*, 8/15/2018		135,000,000		135,000,000
1-month LIBOR minus 0.150%, 1.935%*, 7/16/2018		188,000,000		188,000,000
1-month LIBOR minus 0.090%, 1.94%*, 11/8/2018		70,000,000		70,000,000
1.947%**, 9/4/2018		35,000,000		34,878,667
1-month LIBOR minus 0.135%, 1.95%*, 11/16/2018		190,000,000		190,000,000
1.951%**, 8/22/2018		585,000,000		583,374,220
1.957%**, 9/7/2018		595,000,000		592,830,894
1.957%**, 9/17/2018		25,000,000		24,895,458
1.957%**, 9/28/2018		95,000,000		94,546,715
1-month LIBOR minus 0.125%, 1.959%*, 8/20/2018		220,000,000		220,000,000
1-month LIBOR minus 0.130%, 1.961%*, 10/24/2018		120,000,000		120,000,000
1.962%**, 10/9/2018		25,000,000		24,865,625
1-month LIBOR minus 0.125%, 1.963%*, 6/21/2019		163,500,000		163,500,000
3-month LIBOR minus 0.390%, 1.965%*, 1/22/2019		5,125,000		5,125,000
1-month LIBOR minus 0.110%, 1.974%*, 2/22/2019		224,000,000		224,000,000
1-month LIBOR minus 0.120%, 1.978%*, 10/26/2018		300,000,000		300,000,000
1-month LIBOR minus 0.090%, 1.995%*, 1/18/2019		95,000,000		95,000,000
3-month LIBOR minus 0.330%, 2.005%*, 12/21/2018		155,000,000		155,000,000
1-month LIBOR minus 0.040%, 2.006%*, 7/9/2018		50,000,000		50,000,894
2.008%**, 10/25/2018		25,000,000		24,840,500
3-month LIBOR minus 0.310%, 2.017%*, 3/11/2019		210,000,000		210,000,000
1-month LIBOR minus 0.045%, 2.046%*, 1/24/2019		75,000,000		75,037,273
3-month LIBOR minus 0.250%, 2.058%*, 8/3/2018		168,000,000		168,000,000
2.069%**, 1/4/2019		607,000		600,565
3-month LIBOR minus 0.250%, 2.109%*, 7/30/2018		168,000,000		168,000,000
Federal Home Loan Mortgage Corp.:
0.875%, 10/12/2018		590,000		588,997
1.375%, 2/28/2019		906,000		901,684
1.749%**, 8/9/2018		50,000,000		49,906,562
1.774%**, 7/18/2018		200,000,000		199,834,721
1.779%**, 7/16/2018		56,000,000		55,959,050
1.784%**, 8/9/2018		22,000,000		21,958,053
1.815%**, 7/26/2018		220,000,000		219,726,528
1-month LIBOR minus 0.150%, 1.896%*, 2/12/2019		20,000,000		20,000,000
1.916%**, 8/20/2018		150,000,000		149,606,250
1-month LIBOR minus 0.16%, 1.925%*, 7/19/2018		150,000,000		150,000,000
1-month LIBOR minus 0.100%, 1.93%*, 8/8/2019		87,000,000		87,000,000
3-month LIBOR minus 0.280%, 2.073%*, 8/10/2018		100,000,000		100,000,000
3-month LIBOR minus 0.250%, 2.087%*, 10/10/2018		85,500,000		85,500,000
3-month LIBOR minus 0.250%, 2.109%*, 7/24/2018		965,000		964,962
				9,256,642,567

The accompanying notes are an integral part of the financial statements.

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	Principal Amount ($)		Value ($)
U.S. Treasury Obligations 34.2%
U.S. Treasury Bills:
1.257%**, 9/13/2018		5,000,000		4,987,255
1.832%**, 8/23/2018		300,000,000		299,202,019
1.855%**, 7/26/2018		475,000,000		474,396,353
1.86%**, 8/2/2018		200,000,000		199,673,778
1.872%**, 9/20/2018		155,000,000		154,356,207
1.886%**, 8/23/2018		16,000,000		15,956,187
1.906%**, 9/27/2018		300,000,000		298,621,334
1.916%**, 9/20/2018		125,000,000		124,468,437
1.918%**, 9/20/2018		125,000,000		124,467,875
1.921%**, 9/27/2018		366,000,000		364,304,607
1.924%**, 8/30/2018		120,000,000		119,620,400
1.977%**, 9/20/2018		280,000,000		278,771,500
2.008%**, 10/18/2018		200,000,000		198,801,000
2.009%**, 10/18/2018		85,000,000		84,490,168
2.058% **, 11/23/2018		200,000,000		198,364,722
2.059%**, 11/23/2018		108,500,000		107,612,643
U.S. Treasury Floating Rate Notes:
3-month U.S. Treasury Bill Money Market Yield plus 0.140%, 2.049%*, 1/31/2019		154,000,000		154,185,865
3-month U.S. Treasury Bill Money Market Yield plus 0.170%, 2.079%*, 10/31/2018		1,137,000,000		1,137,955,115
3-month U.S. Treasury Bill Money Market Yield plus 0.174%, 2.083%*, 7/31/2018		1,175,000,000		1,175,242,374
U.S. Treasury Notes, 0.75%, 9/30/2018		4,000,000		3,988,318
				5,519,466,157
Total Government & Agency Obligations (Cost $14,776,108,724)				14,776,108,724
Repurchase Agreements 8.3%
BNP Paribas, 2.1%, dated 6/29/2018, to be repurchased at $212,837,240 on 7/2/2018 (a)		212,800,000		212,800,000
Citigroup Global Markets, Inc., 2.1%, dated 6/29/2018, to be repurchased at $150,026,250 on 7/2/2018 (b)		150,000,000		150,000,000
Fixed Income Clearing Corp., 1.00%, dated 6/29/2018, to be repurchased at $300,025,000 on 7/2/2018 (c)		300,000,000		300,000,000
HSBC Securities, Inc., 2.11%, dated 6/29/2018, to be repurchased at $250,043,958 on 7/2/2018 (d)		250,000,000		250,000,000
Wells Fargo Bank, 2.12%, dated 6/29/2018, to be repurchased at $426,727,375 on 7/2/2018 (e)		426,652,000		426,652,000
Total Repurchase Agreements (Cost $1,339,452,000)				1,339,452,000

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	% of Net Assets		Value ($)
Total Investment Portfolio (Cost $16,115,560,724)		99.9		16,115,560,724
Other Assets and Liabilities, Net		0.1		15,655,398
Net Assets		100.0		16,131,216,122

* Floating rate security. These securities are shown at their current rate as of June 30, 2018.

** Annualized yield at time of purchase; not a coupon rate.

(a) Collateralized by:

Principal Amount ($)		Security	Rate (%)	Maturity Date		Collateral Value ($)
	95,982,500	U.S. Treasury Bonds	2.875–3.125		8/31/2022–5/31/2025		96,482,256
	106,451,100	U.S. Treasury Notes	1.25–2.875		5/15/2043–8/15/2045		107,109,770
	20,849,600	U.S. Treasury STRIPS	Zero Coupon		2/15/2033		13,464,046
	Total Collateral Value						217,056,072

(b) Collateralized by $158,000,000 U.S. Treasury Note, 1.75%, maturing on 03/31/2022 with a value of $153,000,009.

(c) Collateralized by $296,165,000 U.S. Treasury Notes, with the various coupon rates from 2.375–3.625%, with various maturity dates of 8/15/2020–2/15/2021 with a value of $306,003,436.

(d) Collateralized by $245,354,299 Government National Mortgage Association, with the various coupon rates from 3.5–5.5%, with various maturity dates of 11/20/2036–6/20/2048 with a value of $255,001,609.

(e) Collateralized by:

Principal Amount ($)		Security	Rate (%)	Maturity Date	Collateral Value ($)
	135,701,926	FREMF Mortgage Trust	0.1–3.703	11/25/2023–1/25/2046		1,262,614
	452,820	Federal Agricultural Mortgage Corp.	2.85	11/30/2021		455,314
	1,245,824	Federal Home Loan Bank	1.2–2.75	12/20/2018–6/10/2022		1,216,915
	99,000,958	Federal Home Loan Mortgage Corp.	2.00–6.50	11/1/2025–7/1/2048		99,205,939
	294,978,884	Federal National Mortgage Association	1.35–6.625	7/11/2018–8/1/2056		300,807,543
	284	Federal National Mortgage Association STRIPS	Zero Coupon	1/15/2028		207
	70,671,059	Federal National Mortgage Association- Interest Only	3.0–8.0	3/15/2029–8/25/2047		11,677,361
	55,956,981	Freddie Mac Multifamily Structured Pass-Through Certificates	0.815–2.896	3/25/2019–12/25/2041		3,294,853

The accompanying notes are an integral part of the financial statements.

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Principal Amount ($)		Security	Rate (%)	Maturity Date		Collateral Value ($)
	13,050,267	Government National Mortgage Association	2.5–10.00		2/20/2019–5/20/2048		12,796,118
	5,271,712	Tennessee Valley Authority	Zero Coupon–2.875		10/15/2018–9/15/2025		4,468,176
	Total Collateral Value						435,185,040

Interest Only: Interest Only (IO) bonds represent the “interest only” portion of payments on a pool of underlying mortgages or mortgage-backed securities. IO securities are subject to prepayment risk of the pool of underlying mortgages.

LIBOR: London Interbank Offered Rate

STRIPS: Separate Trading of Registered Interest and Principal Securities

Fair Value Measurements

Various inputs are used in determining the value of the Portfolio’s investments. These inputs are summarized in three broad levels. Level 1 includes quoted prices in active markets for identical securities. Level 2 includes other significant observable inputs (including quoted prices for similar securities, interest rates, prepayment speeds and credit risk). Level 3 includes significant unobservable inputs (including the Portfolio’s own assumptions in determining the fair value of investments). The level assigned to the securities valuations may not be an indication of the risk or liquidity associated with investing in those securities. Securities held by the Portfolio are reflected as Level 2 because the securities are valued at amortized cost (which approximates fair value) and, accordingly, the inputs used to determine value are not quoted prices in an active market.

The following is a summary of the inputs used as of June 30, 2018 in valuing the Portfolio’s investments. For information on the Portfolio’s policy regarding the valuation of investments, please refer to the Security Valuation section of Note A in the accompanying Notes to Financial Statements.

Assets	Level 1		Level 2		Level 3		Total
Investments in Securities (f)	$	—	$	14,776,108,724	$	—	$	14,776,108,724
Repurchase Agreements		—		1,339,452,000		—		1,339,452,000
Total	$	—	$	16,115,560,724	$	—	$	16,115,560,724

There have been no transfers between fair value measurement levels during the period ended June 30, 2018.

(f) See Investment Portfolio for additional detailed categorizations.

The accompanying notes are an integral part of the financial statements.

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Statement of Assets and Liabilities

as of June 30, 2018 (Unaudited)
Assets
Investments in non-affiliated securities, valued at amortized cost	$	16,115,560,724
Cash		89,877,991
Interest receivable		15,314,533
Other assets		416,468
Total assets		16,221,169,716
Liabilities
Payable for investment purchased		88,426,577
Accrued investment advisory fee		800,541
Accrued Trustees’ fees		59,032
Other accrued expenses and payables		667,444
Total liabilities		89,953,594
Net assets, at value	$	16,131,216,122

The accompanying notes are an integral part of the financial statements.

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Statement of Operations

for the six months ended June 30, 2018 (Unaudited)
Investment Income
Income:
Interest	$	152,505,763
Expenses:
Management fee		9,125,339
Administration fee		2,800,033
Custodian fee		72,562
Professional fees		140,158
Reports to shareholders		21,438
Trustees’ fees and expenses		523,492
Other		252,428
Total expenses before expense reductions		12,935,450
Expense reductions		(3,772,145	)
Total expenses after expense reductions		9,163,305
Net investment income		143,342,458
Net realized gain (loss) from investments		(30,111	)
Net increase (decrease) in net assets resulting from operations	$	143,312,347

The accompanying notes are an integral part of the financial statements.

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Statements of Changes in Net Assets

Increase (Decrease) in Net Assets	Six Months Ended June 30, 2018 (Unaudited)			Year Ended December 31, 2017
Operations:
Net investment income (loss)	$	143,342,458		$	106,771,143
Net realized gain (loss)		(30,111	)		338,378
Net increase (decrease) in net assets resulting from operations		143,312,347			107,109,521
Capital transactions in shares of beneficial interest:
Proceeds from capital invested		36,244,142,699			64,583,463,238
Value of capital withdrawn		(37,428,704,925	)		(59,493,039,509	)
Net increase (decrease) in net assets from capital transactions in shares of beneficial interest		(1,184,562,226	)		5,090,423,729
Increase (decrease) in net assets		(1,041,249,879	)		5,197,533,250
Net assets at beginning of period		17,172,466,001			11,974,932,751
Net assets at end of period	$	16,131,216,122		$	17,172,466,001

The accompanying notes are an integral part of the financial statements.

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Financial Highlights

	Six Months Ended 6/30/18			Years Ended December 31,
	(Unaudited)			2017		2016		2015		2014		2013
Ratios to Average Net Assets and Supplemental Data
Net assets, end of period ($ millions)		16,131			17,172		11,975		18,021		19,918		20,214
Ratio of expenses before expense reductions (%)		.14	*		.14		.16		.17		.17		.16
Ratio of expenses after expense reductions (%)		.10	*		.11		.11		.14		.14		.14
Ratio of net investment income (%)		1.54	*		.83		.32		.11		.05		.08
Total Return (%)a,b		.75	**		.81		.32		.11		.05		.08

^a Total return would have been lower had certain expenses not been reduced.

^b Total return for the Portfolio was derived from the performance of DWS Government Cash Reserves Fund Institutional.

^* Annualized

^** Not annualized

The accompanying notes are an integral part of the financial statements.

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Notes to Financial Statements (Unaudited)

A. Organization and Significant Accounting Policies

Government Cash Management Portfolio (the “Portfolio”) is registered under the Investment Company Act of 1940, as amended (the “1940 Act”), as an open-end management investment company organized as a New York trust.

The Portfolio is a master fund. A master/feeder fund structure is one in which a fund (a “feeder fund”), instead of investing directly in a portfolio of securities, invests most or all of its investment assets in a separate registered investment company (the “master fund”) with substantially the same investment objective and policies as the feeder fund. Such a structure permits the pooling of assets of two or more feeder funds, preserving separate identities or distribution channels at the feeder fund level. The Portfolio may have several feeder funds, including affiliated DWS feeder funds and unaffiliated feeder funds; with a significant ownership percentage of the Portfolio’s net assets. Investment activities of these feeder funds could have a material impact on the Portfolio. As of June 30, 2018, DWS Government Cash Management Fund, DWS Government Cash Reserves Fund Institutional and DWS Government Money Market Series owned approximately 11%, 2% and 84%, respectively, of the Portfolio.

The Portfolio’s financial statements are prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) which require the use of management estimates. Actual results could differ from those estimates. The Fund qualifies as an investment company under Topic 946 of Accounting Standards Codification of U.S. GAAP. The policies described below are followed consistently by the Portfolio in the preparation of its financial statements.

Security Valuation. Various inputs are used in determining the value of the Portfolio’s investments. These inputs are summarized in three broad levels. Level 1 includes quoted prices in active markets for identical securities. Level 2 includes other significant observable inputs (including quoted prices for similar securities, interest rates, prepayment speeds and credit risk). Level 3 includes significant unobservable inputs (including the Portfolio’s own assumptions in determining the fair value of investments). The level assigned to the securities valuations may not be an indication of the risk or liquidity associated with investing in those securities.

The Portfolio values all securities utilizing the amortized cost method permitted in accordance with Rule 2a-7 under the 1940 Act and certain conditions therein. Under this method, which does not take into account unrealized capital gains or losses on securities, an instrument is initially

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valued at its cost and thereafter assumes a constant accretion/amortization rate to maturity of any discount or premium. Securities held by the Portfolio are reflected as Level 2 because the securities are valued at amortized cost (which approximates fair value) and, accordingly, the inputs used to determine value are not quoted prices in an active market.

Repurchase Agreements. The Portfolio may enter into repurchase agreements, under the terms of a Master Repurchase Agreement, with certain banks and broker/dealers whereby the Portfolio, through its custodian or a sub-custodian bank, receives delivery of the underlying securities, the amount of which at the time of purchase and each subsequent business day is required to be maintained at such a level that the value is equal to at least the principal amount of the repurchase price plus accrued interest. The custodian bank or another designated subcustodian holds the collateral in a separate account until the agreement matures. If the value of the securities falls below the principal amount of the repurchase agreement plus accrued interest, the financial institution deposits additional collateral by the following business day. If the financial institution either fails to deposit the required additional collateral or fails to repurchase the securities as agreed, the Portfolio has the right to sell the securities and recover any resulting loss from the financial institution. If the financial institution enters into bankruptcy, the Portfolio’s claims on the collateral may be subject to legal proceedings.

As of June 30, 2018, the Portfolio held repurchase agreements with a gross value of $1,339,452,000. The value of the related collateral exceeded the value of the repurchase agreements at period end. The detail of the related collateral is included in the footnotes following the Portfolio’s Investment Portfolio.

Federal Income Taxes. The Portfolio is considered a Partnership under the Internal Revenue Code, as amended. Therefore, no federal income tax provision is necessary.

It is intended that the Portfolio’s assets, income and distributions will be managed in such a way that an investor in the Portfolio will be able to satisfy the requirements of Subchapter M of the Code, assuming that the investor invested all of its assets in the Portfolio.

At December 31, 2017, Government Cash Management Portfolio had an aggregate cost of investments for federal income tax purposes of $17,453,872,167.

The Portfolio has reviewed the tax positions for the open tax years as of December 31, 2017 and has determined that no provision for income tax and/or uncertain tax provisions is required in the Portfolio’s financial statements. The Portfolio’s federal tax returns for the prior three fiscal years remain open subject to examination by the Internal Revenue Service.

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Contingencies. In the normal course of business, the Portfolio may enter into contracts with service providers that contain general indemnification clauses. The Portfolio’s maximum exposure under these arrangements is unknown, as this would involve future claims that may be made against the Portfolio that have not yet been made. However, based on experience, the Portfolio expects the risk of loss to be remote.

Other. Investment transactions are accounted for on trade date. Interest income is recorded on the accrual basis. Realized gains and losses from investment transactions are recorded on an identified cost basis. All discounts and premiums are accreted/amortized for both tax and financial reporting purposes.

The Portfolio makes an allocation of its net investment income and realized gains and losses from securities transactions to its investors in proportion to their investment in the Portfolio.

B. Fees and Transactions with Affiliates

Management Agreement. Under the Investment Management Agreement with DWS Investment Management Americas, Inc. (formerly Deutsche Investment Management Americas Inc.) (“DIMA” or the “Advisor”), an indirect, wholly owned subsidiary of DWS Group GmbH & Co. KGaA (“DWS Group”), the Advisor determines the securities, instruments and other contracts relating to investments to be purchased, sold or entered into by the Portfolio.

Under the Investment Management Agreement, the Portfolio pays the Advisor a monthly management fee based on its average daily net assets, computed and accrued daily and payable monthly, at the following annual rates:

First $3.0 billion of the Portfolio’s average daily net assets	.1200%
Next $4.5 billion of such net assets	.1025%
Over $7.5 billion of such net assets	.0900%

Accordingly, for the six months ended June 30, 2018, the fee pursuant to the Investment Management Agreement was equivalent to an annualized rate (exclusive of any applicable waivers/reimbursements) of 0.10% of the Fund’s average daily net assets.

For the period from January 1, 2018 through September 30, 2018, the Advisor has contractually agreed to waive its fees and/or reimburse certain operating expenses to the extent necessary to maintain the total annual operating expenses (excluding certain expenses such as extraordinary expenses, taxes, brokerage and interest) at 0.14% of the Portfolio’s average daily net assets.

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For the period from January 1, 2018 through April 10, 2018, the Advisor had voluntarily agreed to waive its fees and/or reimburse certain operating expenses to the extent necessary to maintain the total annual operating expenses (excluding certain expenses such as extraordinary expenses, taxes, brokerage and interest) at 0.10% of the Portfolio’s average daily net assets.

For the period from April 11, 2018 through April 26, 2018, the Advisor had voluntarily agreed to waive its fees and/or reimburse certain operating expenses to the extent necessary to maintain the total annual operating expenses (excluding certain expenses such as extraordinary expenses, taxes, brokerage and interest) at 0.08% of the Portfolio’s average daily net assets.

Effective April 27, 2018 through June 30, 2018, the Advisor has voluntarily agreed to waive its fees and/or reimburse certain operating expenses to the extent necessary to maintain the total annual operating expenses (excluding certain expenses such as extraordinary expenses, taxes, brokerage and interest) at 0.10% of the Portfolio’s average daily net assets. This voluntary waiver or reimbursement may be terminated at any time at the option of the Advisor.

For the six months ended June 30, 2018, fees waived and/or expenses reimbursed are $3,772,145.

Administration Fee. Pursuant to an Administrative Services Agreement, DIMA provides most administrative services to the Portfolio. For all services provided under the Administrative Services Agreement, the Portfolio pays the Advisor an annual fee (“Administration Fee”) of 0.03% of the Portfolio’s average daily net assets, computed and accrued daily and payable monthly. For the six months ended June 30, 2018, the Administration Fee was $2,800,033, of which $491,191 is unpaid.

Filing Service Fees. Under an agreement with DIMA, DIMA is compensated for providing certain regulatory filing services to the Portfolio. For the six months ended June 30, 2018, the amount charged to the Portfolio by DIMA included in the Statement of Operations under “Reports to shareholders” aggregated $751, all of which is unpaid.

Trustees’ Fees and Expenses. The Portfolio paid retainer fees to each Trustee not affiliated with the Advisor, plus specified amounts to the Board Chairperson and Vice Chairperson and to each committee Chairperson.

C. Line of Credit

The Portfolio and other affiliated funds (the “Participants”) share in a $400 million revolving credit facility provided by a syndication of banks. The Portfolio may borrow for temporary or emergency purposes, including the meeting of redemption requests that otherwise might require the

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untimely disposition of securities. The Participants are charged an annual commitment fee which is allocated based on net assets, among each of the Participants. Interest is calculated at a rate per annum equal to the sum of the Federal Funds Rate plus 1.25 percent plus if the one-month LIBOR exceeds the Federal Funds Rate, the amount of such excess. The Portfolio may borrow up to a maximum of 33 percent of its net assets under the agreement. The Portfolio had no outstanding loans at June 30, 2018.

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Advisory Agreement Board Considerations and Fee Evaluation

Deutsche Government Cash Management Fund (now known as DWS Government Cash Management Fund) (the “Fund”), a series of Deutsche Money Market Trust (now known as Deutsche DWS Money Market Trust), invests substantially all of its assets in Government Cash Management Portfolio (the “Portfolio”) in order to achieve its investment objective. The Portfolio’s Board of Trustees approved the renewal of the Portfolio’s investment management agreement (the “Portfolio Agreement”) with Deutsche Investment Management Americas Inc. (now known as DWS Investment Management Americas, Inc.) (“DIMA”) and the Fund’s Board of Trustees (which consists of the same members as the Board of Trustees of the Portfolio) approved the renewal of the Fund’s investment management agreement with DIMA (the “Fund Agreement,” and together with the Portfolio Agreement, the “Agreements”) in September 2017. The Portfolio’s Board of Trustees and the Fund’s Board of Trustees are collectively referred to as the “Board” or “Trustees.”

In terms of the process that the Board followed prior to approving the Agreements, shareholders should know that:

– During the entire process, all of the Portfolio’s and the Fund’s Trustees were independent of DIMA and its affiliates (the “Independent Trustees”).

– The Board met frequently during the past year to discuss fund matters and dedicated a substantial amount of time to contract review matters. Over the course of several months, the Board’s Contract Committee reviewed extensive materials received from DIMA, independent third parties and independent counsel. These materials included an analysis of performance, fees and expenses, and profitability from a fee consultant retained by the Independent Trustees (the “Fee Consultant”). Based on its evaluation of the information provided, the Contract Committee presented its findings and recommendations to the Board. The Board then reviewed the Contract Committee’s findings and recommendations.

– The Board also received extensive information throughout the year regarding performance of the Portfolio and the Fund.

– The Independent Trustees regularly met privately with counsel to discuss contract review and other matters. In addition, the Independent Trustees were advised by the Fee Consultant in the course of their review of the Portfolio’s and the Fund’s contractual arrangements and considered a comprehensive report prepared by the Fee Consultant in connection with their deliberations.

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– In connection with reviewing the Agreements, the Board also reviewed the terms of the Fund’s distribution agreement, administrative services agreement, transfer agency agreement and other material service agreements.

In connection with the contract review process, the Contract Committee and the Board considered the factors discussed below, among others. The Board also considered that DIMA and its predecessors have managed the Portfolio and the Fund since their inception, and the Board believes that a long-term relationship with a capable, conscientious advisor is in the best interests of the Portfolio and the Fund. The Board considered, generally, that shareholders chose to invest or remain invested in the Fund knowing that DIMA managed the Portfolio and the Fund. DIMA is part of Deutsche Bank AG’s (“Deutsche Bank”) Asset Management (“Deutsche AM”) division. Deutsche AM is a global asset management business that offers a wide range of investing expertise and resources, including research capabilities in many countries throughout the world.

As part of the contract review process, the Board carefully considered the fees and expenses of each Deutsche fund overseen by the Board in light of the fund’s performance. In many cases, this led to the negotiation and implementation of expense caps. As part of these negotiations, the Board indicated that it would consider relaxing these caps in future years following sustained improvements in performance, among other considerations.

While shareholders may focus primarily on fund performance and fees, the Board considers these and many other factors, including the quality and integrity of DIMA’s personnel and administrative support services provided by DIMA, such as back-office operations, fund valuations, and compliance policies and procedures.

Nature, Quality and Extent of Services. The Board considered the terms of the Agreements, including the scope of advisory services provided under the Agreements. The Board noted that, under the Agreements, DIMA provides portfolio management services to the Portfolio and the Fund and that, pursuant to separate administrative services agreements, DIMA provides administrative services to the Portfolio and the Fund. The Board considered the experience and skills of senior management and investment personnel and the resources made available to such personnel. The Board reviewed the Portfolio’s and the Fund’s performance over short-term and long-term periods and compared those returns to various agreed-upon performance measures, including a peer universe compiled using information supplied by iMoneyNet, an independent fund data service. The Board also noted that it has put into place a process of identifying “Funds in Review” (e.g., funds performing poorly relative to a peer universe), and receives additional reporting from

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DIMA regarding such funds and, where appropriate, DIMA’s plans to address underperformance. The Board believes this process is an effective manner of identifying and addressing underperforming funds. Based on the information provided, the Board noted that, for the one- and three-year periods ended December 31, 2016, the Fund’s gross performance (Institutional Shares) was in the 1st quartile of the applicable iMoneyNet universe (the 1st quartile being the best performers and the 4th quartile being the worst performers).

Fees and Expenses. The Board considered the Portfolio’s and the Fund’s investment management fee schedules, the Fund’s operating expenses and total expense ratios, and comparative information provided by Broadridge Financial Solutions, Inc. (“Broadridge”) and the Fee Consultant regarding investment management fee rates paid to other investment advisors by similar funds (1st quartile being the most favorable and 4th quartile being the least favorable). With respect to management fees paid to other investment advisors by similar funds, the Board noted that the contractual fee rates paid by the Portfolio and the Fund, which include 0.03% and 0.10% fees paid to DIMA under the respective administrative services agreements, were higher than the median (3rd quartile) of the applicable Broadridge peer group (based on Broadridge data provided as of December 31, 2016). The Board noted that, although shareholders of the Fund indirectly bear the Portfolio’s management fee, the Fund does not charge an additional investment management fee. Based on Broadridge data provided as of December 31, 2016, the Board noted that the Fund’s total (net) operating expenses, which include Portfolio expenses allocated to the Fund, were higher than the median of the applicable Broadridge expense universe for Institutional Shares (4th quartile). The Board noted the expense limitation agreed to by DIMA. The Board also noted the voluntary fee waivers implemented by DIMA to ensure the Fund maintained a positive yield. The Board considered the management fee rate as compared to fees charged by DIMA to comparable Deutsche U.S. registered funds (“Deutsche Funds”) and considered differences between the Portfolio and the Fund and the comparable Deutsche Funds. The information requested by the Board as part of its review of fees and expenses also included information about institutional accounts (including any sub-advised funds and accounts) and funds offered primarily to European investors (“Deutsche Europe funds”) managed by Deutsche AM. The Board noted that DIMA indicated that Deutsche AM does not manage any institutional accounts or Deutsche Europe funds comparable to the Portfolio and the Fund. The Board considered that the Portfolio’s management fee was reduced by 0.03% at all breakpoint levels in connection with the restructuring of the Portfolio and the Fund into government money market funds in 2016.

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On the basis of the information provided, the Board concluded that management fees were reasonable and appropriate in light of the nature, quality and extent of services provided by DIMA.

Profitability. The Board reviewed detailed information regarding revenues received by DIMA under the Agreements. The Board considered the estimated costs to DIMA, and pre-tax profits realized by DIMA, from advising the Deutsche Funds, as well as estimates of the pre-tax profits attributable to managing the Fund in particular. The Board also received information regarding the estimated enterprise-wide profitability of DIMA and its affiliates with respect to all fund services in totality and by fund. The Board and the Fee Consultant reviewed DIMA’s methodology in allocating its costs to the management of the Fund. Based on the information provided, the Board concluded that the pre-tax profits realized by DIMA in connection with the management of the Fund were not unreasonable. The Board also reviewed certain publicly available information regarding the profitability of certain similar investment management firms. The Board noted that, while information regarding the profitability of such firms is limited (and in some cases is not necessarily prepared on a comparable basis), DIMA and its affiliates’ overall profitability with respect to the Deutsche Funds (after taking into account distribution and other services provided to the funds by DIMA and its affiliates) was lower than the overall profitability levels of most comparable firms for which such data was available.

Economies of Scale. The Board considered whether there are economies of scale with respect to the management of the Portfolio and the Fund and whether the Portfolio and the Fund benefit from any economies of scale. The Board noted that the Portfolio’s and the Fund’s investment management fee schedule includes fee breakpoints. The Board concluded that the Portfolio’s and the Fund’s fee schedule represents an appropriate sharing between the Portfolio and the Fund and DIMA of such economies of scale as may exist in the management of the Portfolio and the Fund at current asset levels.

Other Benefits to DIMA and Its Affiliates. The Board also considered the character and amount of other incidental benefits received by DIMA and its affiliates, including any fees received by DIMA for administrative services provided to the Portfolio and the Fund and any fees received by an affiliate of DIMA for transfer agency services provided to the Fund. The Board also considered benefits to DIMA related to brokerage and soft-dollar allocations, including allocating brokerage to pay for research generated by parties other than the executing broker dealers, which pertain primarily to funds investing in equity securities. In addition, the Board considered the incidental public relations benefits to DIMA related to Deutsche Funds advertising and cross-selling opportunities among

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DIMA products and services. The Board considered these benefits in reaching its conclusion that the Portfolio’s and the Fund’s management fees were reasonable.

Compliance. The Board considered the significant attention and resources dedicated by DIMA to documenting and enhancing its compliance processes in recent years. The Board noted in particular (i) the experience, seniority and time commitment of the individuals serving as DIMA’s and the Fund’s chief compliance officers; (ii) the large number of DIMA compliance personnel; and (iii) the substantial commitment of resources by DIMA and its affiliates to compliance matters.

Based on all of the information considered and the conclusions reached, the Board unanimously determined that the continuation of the Agreements is in the best interests of the Portfolio and the Fund. In making this determination, the Board did not give particular weight to any single factor identified above. The Board considered these factors over the course of numerous meetings, certain of which were in executive session with only the Independent Trustees and counsel present. It is possible that individual Independent Trustees may have weighed these factors differently in reaching their individual decisions to approve the continuation of the Agreements.

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Account Management Resources

Automated Information Line	Institutional Investor Services (800) 730-1313 Personalized account information, information on other DWS funds and services via touchtone telephone and the ability to exchange or redeem shares.
Web Site	liquidity.dws.com View your account transactions and balances, trade shares, monitor your asset allocation, subscribe to fund and account updates by e-mail, and change your address, 24 hours a day. Obtain prospectuses and applications, news about DWS funds, insight from DWS economists and investment specialists and access to DWS fund account information.
For More Information	(800) 730-1313, option 1 To speak with a fund service representative.
Written Correspondence	DWS PO Box 219210 Kansas City, MO 64121-9210
Proxy Voting	The Fund’s policies and procedures for voting proxies for portfolio securities and information about how the Fund voted proxies related to its portfolio securities during the most recent 12-month period ended June 30 are available on our Web site — dws.com/en-us/resources/proxy-voting — or on the SEC’s Web site — sec.gov. To obtain a written copy of the Fund’s policies and procedures without charge, upon request, call us toll free at (800) 728-3337.
Portfolio Holdings	Following the Fund’s fiscal first and third quarter-end, a complete portfolio holdings listing is filed with the SEC on Form N-Q. In addition, each month, information about the Fund and its portfolio holdings is filed with the SEC on Form N-MFP. The SEC delays the public availability of the information filed on Form N-MFP for 60 days after the end of the reporting period included in the filing. These forms will be available on the SEC’s Web site at sec.gov, and they may also be reviewed and copied at the SEC’s Public Reference Room in Washington, D.C. Information on the operation of the SEC’s Public Reference Room may be obtained by calling (800) SEC-0330. The Fund’s portfolio holdings are also posted on dws.com from time to time. Please see the Fund’s current prospectus for more information.
Principal Underwriter	If you have questions, comments or complaints, contact: DWS Distributors, Inc. 222 South Riverside Plaza Chicago, IL 60606-5808 (800) 621-1148

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Investment Management	DWS Investment Management Americas, Inc. (“DIMA” or the “Advisor”), which is part of the DWS Group GmbH & Co. KGaA (“DWS Group”), is the investment advisor for the Fund. DIMA and its predecessors have more than 90 years of experience managing mutual funds and DIMA provides a full range of investment advisory services to both institutional and retail clients. DIMA is an indirect, wholly owned subsidiary of DWS Group. DWS Group is a global organization that offers a wide range of investing expertise and resources, including hundreds of portfolio managers and analysts and an office network that reaches the world’s major investment centers. This wellresourced global investment platform brings together a wide variety of experience and investment insight across industries, regions, asset classes and investing styles.
Nasdaq Symbol	BICXX
CUSIP Number	25160K 306
Fund Number	541

DWS Government Cash Management Fund | 35

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Privacy Statement

FACTS	What Does DWS Do With Your Personal Information?
Why?	Financial companies choose how they share your personal information. Federal law gives consumers the right to limit some but not all sharing. Federal law also requires us to tell you how we collect, share and protect your personal information. Please read this notice carefully to understand what we do.
What?	The types of personal information we collect and share can include: –SocialSecurity number – Account balances – Purchase and transaction history – Bank account information – Contact information such as mailing address, e-mail address and telephone number
How?	All financial companies need to share customers’ personal information to run their everyday business. In the section below, we list the reasons financial companies can share their customers’ personal information, the reasons DWS chooses to share and whether you can limit this sharing.

Reasons we can share your personal information	Does DWS share?	Can you limit this sharing?
For our everyday business purposes — such as to process your transactions, maintain your account(s), respond to court orders or legal investigations	Yes		No
For our marketing purposes — to offer our products and services to you	Yes		No
For joint marketing with other financial companies	No		We do not share
For our affiliates’ everyday business purposes — information about your transactions and experiences	No		We do not share
For our affiliates’ everyday business purposes — information about your creditworthiness	No		We do not share
For non-affiliates to market to you	No		We do not share

Questions? Call (800) 728-3337 or e-mail us at service@dws.com

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Who we are
Who is providing this notice?	DWS Distributors, Inc; DWS Investment Management Americas, Inc.; DWS Trust Company; the DWS Funds
What we do
How does DWS protect my personal information?	To protect your personal information from unauthorized access and use, we use security measures that comply with federal law. These measures include computer safeguards and secured files and buildings.
How does DWS collect my personal information?	We collect your personal information, for example, when you: – open an account – give us your contact information – provide bank account information for ACH or wire transactions – tell us where to send money – seek advice about your investments
Why can’t I limit all sharing?	Federal law gives you the right to limit only – sharing for affiliates’ everyday business purposes – information about your creditworthiness – affiliates from using your information to market to you – sharing for non-affiliates to market to you State laws and individual companies may give you additional rights to limit sharing.
Definitions
Affiliates	Companies related by common ownership or control. They can be financial or non-financial companies. Our affiliates include financial companies with the DWS or Deutsche Bank (“DB”) name, such as DB AG Frankfurt.
Non-affiliates	Companies not related by common ownership or control. They can be financial and non-financial companies. Non-affiliates we share with include account service providers, service quality monitoring services, mailing service providers and verification services to help in the fight against money laundering and fraud.
Joint marketing	A formal agreement between non-affiliated financial companies that together market financial products or services to you. DWS does not jointly market.

Rev. 3/2018, as amended 7/2018

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Notes

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Notes

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DGCMF-3

(R-028295-7 8/18)

Table of Contents

June 30, 2018

Semiannual Report

to Shareholders

DWS Government Cash Reserves Fund Institutional

(formerly Deutsche Government Cash Reserves Fund Institutional)

Table of Contents

Contents

DWS Government Cash Reserves Fund Institutional
3	Portfolio Summary
4	Statement of Assets and Liabilities
5	Statement of Operations
6	Statements of Changes in Net Assets
7	Financial Highlights
8	Notes to Financial Statements
12	Information About Your Fund’s Expenses
Government Cash Management Portfolio
15	Investment Portfolio
20	Statement of Assets and Liabilities
21	Statement of Operations
22	Statements of Changes in Net Assets
23	Financial Highlights
24	Notes to Financial Statements
29	Advisory Agreement Board Considerations and Fee Evaluation
34	Account Management Resources
36	Privacy Statement

This report must be preceded or accompanied by a prospectus. To obtain a summary prospectus, if available, or prospectus for any of our funds, refer to the Account Management Resources information provided in the back of this booklet. We advise you to consider the Fund’s objectives, risks, charges and expenses carefully before investing. The summary prospectus and prospectus contain this and other important information about the Fund. Please read the prospectus carefully before you invest.

You could lose money by investing in the Fund. Although the Fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so. An investment in the Fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The Fund’s sponsor has no legal obligation to provide financial support to the Fund, and you should not expect that the sponsor will provide financial support to the Fund at any time. You should not rely on or expect the Advisor to enter into support agreements or take other actions to maintain the Fund’s $1.00 share price. The credit quality of the Fund’s holdings can change rapidly in certain markets, and the default of a single holding could have an adverse impact on the Fund’s share price. The Fund’s share price can also be negatively affected during periods of high redemption pressures and/or illiquid markets. The actions of a few large investors of the Fund may have a significant adverse effect on the share price of the Fund. Please read the prospectus for specific details regarding the Fund’s risk profile.

The brand DWS represents DWS Group GmbH & Co. KGaA and any of its subsidiaries such as DWS Distributors, Inc. which offers investment products or DWS Investment Management Americas, Inc. and RREEF America L.L.C. which offer advisory services.

NOT FDIC/NCUA INSURED     NO BANK GUARANTEE     MAY LOSE VALUE NOT A DEPOSIT     NOT INSURED BY ANY FEDERAL GOVERNMENT AGENCY

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Portfolio Summary		(Unaudited)
Asset Allocation (As a % of Investment Portfolio)	6/30/18		12/31/17
Government & Agency Obligations		92%		90%
Repurchase Agreements		8%		10%
		100%		100%
Weighted Average Maturity	6/30/18		12/31/17
DWS Government Cash Reserves Fund Institutional		32 days		43 days
Government & Agency Institutional*		29 days		31 days

* The Fund is compared to its respective iMoneyNet category: Government & Agency Institutional — Category includes the most broadly based of the government institutional funds. These funds may invest in U.S. Treasury securities, securities issued or guaranteed by the U.S. Government or its agencies or instrumentalities.

Weighted average maturity, also known as effective maturity, is the weighted average of the maturity date of bonds held by the Fund taking into consideration any available maturity shortening features.

Portfolio holdings and characteristics are subject to change.

For more complete details about the portfolio’s holdings, see page 15. A quarterly Fact Sheet is available on liquidity.dws.com/US/products/fund_facts_prospectus_l2.jsp or upon request. Please see the Account Management Resources section on page 34 for contact information.

DWS Government Cash Reserves Fund Institutional | 3

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Statement of Assets and Liabilities

as of June 30, 2018 (Unaudited)
Assets
Investment in Government Cash Management Portfolio, at value	$	369,257,827
Other assets		13,322
Total assets		369,271,149
Liabilities
Distributions payable		129,408
Accrued Trustees’ fees		456
Other accrued expenses and payables		85,706
Total liabilities		215,570
Net assets, at value	$	369,055,579
Net Assets Consist of
Undistributed net investment income		1,875
Accumulated net realized gain (loss)		30,275
Paid-in capital		369,023,429
Net assets, at value	$	369,055,579
Net Asset Value
Net Asset Value, offering and redemption price per share ($369,055,579 ÷ 369,336,382 outstanding shares of beneficial interest, $.01 par value, unlimited number of shares authorized)	$	1.00

The accompanying notes are an integral part of the financial statements.

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Statement of Operations

for the six months ended June 30, 2018 (Unaudited)
Investment Income
Income and expenses allocated from Government Cash Management Portfolio:
Interest	$	4,267,143
Expenses*		(261,533	)
Net investment income allocated from Government Cash Management Portfolio		4,005,610
Expenses:
Administration fee		265,735
Services to shareholders		16,535
Service fees		36,307
Professional fees		20,336
Reports to shareholders		9,411
Registration fees		13,965
Trustees’ fees and expenses		2,331
Other		22,379
Total expenses before expense reductions		386,999
Expense reductions		(90,460	)
Total expenses after expense reductions		296,539
Net investment income		3,709,071
Net realized gain (loss) allocated from Government Cash Management Portfolio		143
Net increase (decrease) in net assets resulting from operations	$	3,709,214

* Net of $105,975 Advisor reimbursement allocated from Government Cash Management Portfolio for the six months ended June 30, 2018.

The accompanying notes are an integral part of the financial statements.

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Statements of Changes in Net Assets

	Six Months Ended June 30, 2018			Year Ended December 31,
Increase (Decrease) in Net Assets	(Unaudited)			2017
Operations:
Net investment income	$	3,709,071		$	5,477,994
Net realized gain (loss)		143			30,132
Net increase (decrease) in net assets resulting from operations		3,709,214			5,508,126
Distributions to shareholders from:
Net investment income		(3,709,743	)		(5,477,632	)
Fund share transactions:
Proceeds from shares sold		3,292,866,140			12,461,817,208
Reinvestment of distributions		1,864,455			3,021,269
Payments for shares redeemed		(3,426,588,078	)		(12,563,944,379	)
Net increase (decrease) in net assets from Fund share transactions		(131,857,483	)		(99,105,902	)
Increase (decrease) in net assets		(131,858,012	)		(99,075,408	)
Net assets at beginning of period		500,913,591			599,988,999
Net assets at end of period (including undistributed net investment income of $1,875 and $2,547, respectively)	$	369,055,579		$	500,913,591
Other Information
Shares outstanding at beginning of period		501,193,865			600,299,767
Shares sold		3,292,866,140			12,461,817,208
Shares issued to shareholders in reinvestment of distributions		1,864,455			3,021,269
Shares redeemed		(3,426,588,078	)		(12,563,944,379	)
Net increase (decrease) in Fund shares		(131,857,483	)		(99,105,902	)
Shares outstanding at end of period		369,336,382			501,193,865

The accompanying notes are an integral part of the financial statements.

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Financial Highlights

	Six Months Ended 6/30/18				Years Ended December 31,
	(Unaudited)				2017			2016			2015			2014			2013
Selected Per Share Data
Net asset value, beginning of period		$	1.00		$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Income from investment operations:
Net investment income			.007			.007			.002			.000	***		.000	***		.000	***
Net realized gain (loss)			.000	***		.000	***		.000	***		.000	***		.000	***		.000	***
Total from investment operations			.007			.007			.002			.000	***		.000	***		.000	***
Less distributions from:
Net investment income			(.007	)		(.007	)		(.002	)		(.000	)***		(.000	)***		(.000	)***
Net asset value, end of period		$	1.00		$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Total Return (%)a			.70	**		.71			.22			.04			.01			.02
Ratios to Average Net Assets and Supplemental Data
Net assets, end of period ($ millions)			369			501			600			1,927			1,009			1,367
Ratio of expenses before expense reductions, including expenses allocated from Government Cash Management Portfolio (%)			.28	*		.28			.28			.28			.28			.27
Ratio of expenses after expense reductions, including expenses allocated from Government Cash Management Portfolio (%)			.21	*		.21			.21			.21			.18			.20
Ratio of net investment income (%)			1.40	*		.68			.22			.04			.01			.02

^a Total return would have been lower had certain expenses not been reduced.

* Annualized

** Not annualized

*** Amount is less than $.0005.

The accompanying notes are an integral part of the financial statements.

DWS Government Cash Reserves Fund Institutional | 7

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Notes to Financial Statements (Unaudited)

A. Organization and Significant Accounting Policies

DWS Government Cash Reserves Fund Institutional (formerly Deutsche Government Cash Reserves Fund Institutional) (the “Fund”) is a diversified series of Deutsche DWS Money Market Trust (formerly Deutsche Money Market Trust) (the “Trust”), which is registered under the Investment Company Act of 1940, as amended (the “1940 Act”), as an open-end management investment company organized as a Massachusetts business trust.

The Fund is a feeder fund that seeks to achieve its investment objective by investing substantially all of its investable assets in a master portfolio, the Government Cash Management Portfolio (the “Portfolio”), an open-end management investment company registered under the 1940 Act and organized as a New York trust advised by DWS Investment Management Americas, Inc. (formerly Deutsche Investment Management Americas Inc.) (“DIMA” or the “Advisor”), an indirect, wholly owned subsidiary of DWS Group GmbH & Co. KGaA (“DWS Group”). A master/feeder fund structure is one in which a fund (a “feeder fund”), instead of investing directly in a portfolio of securities, invests most or all of its investment assets in a separate registered investment company (the “master fund”) with substantially the same investment objective and policies as the feeder fund. Such a structure permits the pooling of assets of two or more feeder funds, preserving separate identities or distribution channels at the feeder fund level. At June 30, 2018, the Fund owned approximately 2% of the Portfolio.

The Fund’s financial statements are prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) which require the use of management estimates. Actual results could differ from those estimates. The Fund qualifies as an investment company under Topic 946 of Accounting Standards Codification of U.S. GAAP. The policies described below are followed consistently by the Fund in the preparation of its financial statements. The financial statements of the Portfolio, including the Investment Portfolio, are contained elsewhere in this report and should be read in conjunction with the Fund’s financial statements.

Security Valuation. The Fund records its investment in the Portfolio at value, which reflects its proportionate interest in the net assets of the Portfolio and is categorized as Level 1. Valuation of the securities held by the Portfolio is discussed in the notes to the Portfolio’s financial statements included elsewhere in this report.

Disclosure about the classification of fair value measurements is included in a table following the Portfolio’s Investment Portfolio.

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Federal Income Taxes. The Fund’s policy is to comply with the requirements of the Internal Revenue Code, as amended, which are applicable to regulated investment companies, and to distribute all of its taxable income to its shareholders.

The Fund has reviewed the tax positions for the open tax years as of December 31, 2017, and has determined that no provision for income tax and/or uncertain tax provisions is required in the Fund’s financial statements. The Fund’s federal tax returns for the prior three fiscal years remain open subject to examination by the Internal Revenue Service.

Distribution of Income and Gains. Net investment income of the Fund is declared as a daily dividend and is distributed to shareholders monthly. The Fund may take into account capital gains and losses in its daily dividend declarations. The Fund may also make additional distributions for tax purposes if necessary.

Permanent book and tax differences relating to shareholder distributions will result in reclassifications to paid in capital. Temporary book and tax differences will reverse in a subsequent period. There were no significant book to tax differences for the Fund.

The tax character of current year distributions will be determined at the end of the current fiscal year.

Contingencies. In the normal course of business, the Fund may enter into contracts with service providers that contain general indemnification clauses. The Fund’s maximum exposure under these arrangements is unknown, as this would involve future claims that may be made against the Fund that have not yet been made. However, based on experience, the Fund expects the risk of loss to be remote.

Other. The Fund receives an allocation of the Portfolio’s net investment income and net realized gains and losses in proportion to its investment in the Portfolio. Expenses directly attributed to a fund are charged to that fund, while expenses which are attributable to the Trust are allocated among the funds in the Trust on the basis of relative net assets.

B. Fees and Transactions with Affiliates

Management Agreement. Under the Investment Management Agreement with DWS Investment Management Americas, Inc. (formerly Deutsche Investment Management Americas Inc.) (“DIMA” or the “Advisor”), an indirect, wholly owned subsidiary of DWS Group GmbH & Co. KGaA (“DWS Group”), the Advisor serves as the investment manager to the Fund. The Advisor receives a management fee from the Portfolio pursuant to the master/feeder structure listed above in Note A.

For the period from January 1, 2018 through April 30, 2019, DIMA has contractually agreed to waive its fees and/or reimburse certain operating

DWS Government Cash Reserves Fund Institutional | 9

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expenses of the Fund, including expenses of the Portfolio allocated to the Fund, to the extent necessary to maintain the total annual operating expenses (excluding certain expenses such as extraordinary expenses, taxes, brokerage and interest) at 0.21% of the Fund’s average daily net assets.

For the six months ended June 30, 2018, fees waived and/or expenses

reimbursed are $90,460.

Administration Fee. Pursuant to an Administrative Services Agreement, DIMA provides most administrative services to the Fund. For all services provided under the Administrative Services Agreement, the Fund pays the Advisor an annual fee (“Administration Fee”) of 0.10% of the Fund’s average daily net assets, computed and accrued daily and payable monthly. For the six months ended June 30, 2018, the Administration Fee was $265,735, of which $42,500 is unpaid.

Service Provider Fees. DWS Service Company (“DSC”), an affiliate of the Advisor, is the transfer agent, dividend-paying agent and shareholder service agent for the Fund. Pursuant to a sub-transfer agency agreement between DSC and DST Systems, Inc. (“DST”), DSC has delegated certain transfer agent, dividend-paying agent and shareholder service agent functions to DST. DSC compensates DST out of the shareholder servicing fee it receives from the Fund. For the six months ended June 30, 2018, the amount charged to the Fund by DSC aggregated $14,754, all of which was waived.

Shareholder Servicing Fee. DWS Distributors, Inc. (“DDI”), an affiliate of the Advisor, provides information and administrative services for a fee (“Service Fee”) to shareholders at an annual rate of up to 0.25% of average daily net assets. DDI in turn has various agreements with financial services firms that provide these services and pay these fees based upon the assets of shareholder accounts the firms service. For the six months ended June 30, 2018, the Service Fee was as follows:

	Total Aggregated		Unpaid at June 30, 2018		Annualized Rate
DWS Government Cash Reserves Fund Institutional	$	36,307	$	3,387		.01	%

Typesetting and Filing Service Fees. Under an agreement with DIMA, DIMA is compensated for providing certain pre-press and regulatory filing services to the Fund. For the six months ended June 30, 2018, the amount charged to the Fund by DIMA included in the Statement of Operations under “Reports to shareholders” aggregated $7,530, all of which is unpaid.

Trustees’ Fees and Expenses. The Fund paid retainer fees to each Trustee not affiliated with the Advisor, plus specified amounts to the Board Chairperson and Vice Chairperson and to each committee Chairperson.

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C. Concentration of Ownership

From time to time, the Fund may have a concentration of several shareholder accounts holding a significant percentage of shares outstanding. Investment activities of these shareholders could have a material impact on the Fund.

At June 30, 2018, there were two shareholder accounts that held approximately 38% and 31% of the outstanding shares of the Fund, respectively.

D. Name Changes

In connection with adoption of the DWS brand, effective July 2, 2018, Deutsche Investment Management Americas Inc., the Advisor, was renamed to DWS Investment Management Americas, Inc. In addition, the “Deutsche Funds” became known as the “DWS Funds.” As a result, Deutsche Government Cash Reserves Fund Institutional was renamed DWS Government Cash Reserves Fund Institutional.

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Information About Your Fund’s Expenses

As an investor of the Fund, you incur two types of costs: ongoing expenses and transaction costs. Ongoing expenses include management fees and other Fund expenses. Examples of transaction costs include account maintenance fees, which are not shown in this section. The following tables are intended to help you understand your ongoing expenses (in dollars) of investing in the Fund and to help you compare these expenses with the ongoing expenses of investing in other mutual funds. In the most recent six-month period, the Fund limited these expenses; had it not done so, expenses would have been higher. The example in the table is based on an investment of $1,000 invested at the beginning of the six-month period and held for the entire period (January 1, 2018 to June 30, 2018).

The tables illustrate your Fund’s expenses in two ways:

– Actual Fund Return. This helps you estimate the actual dollar amount of ongoing expenses (but not transaction costs) paid on a $1,000 investment in the Fund using the Fund’s actual return during the period. To estimate the expenses you paid over the period, simply divide your account value by $1,000 (for example, an $8,600 account value divided by $1,000 = 8.6), then multiply the result by the number in the “Expenses Paid per $1,000” line under the share class you hold.

– Hypothetical 5% Fund Return. This helps you to compare your Fund’s ongoing expenses (but not transaction costs) with those of other mutual funds using the Fund’s actual expense ratio and a hypothetical rate of return of 5% per year before expenses. Examples using a 5% hypothetical fund return may be found in the shareholder reports of other mutual funds. The hypothetical account values and expenses may not be used to estimate the actual ending account balance or expenses you paid for the period.

Please note that the expenses shown in these tables are meant to highlight your ongoing expenses only and do not reflect any transaction costs. The “Expenses Paid per $1,000” line of the tables is useful in comparing ongoing expenses only and will not help you determine the relative total expense of owning different funds. If these transaction costs had been included, your costs would have been higher.

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Expenses and Value of a $1,000 Investment for the six months ended June 30, 2018 (Unaudited)
Actual Fund Return*
Beginning Account Value 1/1/18	$	1,000.00
Ending Account Value 6/30/18	$	1,007.05
Expenses Paid per $1,000**	$	1.05
Hypothetical 5% Fund Return
Beginning Account Value 1/1/18	$	1,000.00
Ending Account Value 6/30/18	$	1,023.75
Expenses Paid per $1,000**	$	1.05

* Expenses include amounts allocated proportionally from the master portfolio.

** Expenses are equal to the Fund’s annualized expense ratio, multiplied by the average account value over the period, multiplied by 181 (the number of days in the most recent six-month period), then divided by 365.

Annualized Expense Ratio
DWS Government Cash Reserves Fund Institutional	.21%

For more information, please refer to the Fund’s prospectus.

For an analysis of the fees associated with an investment in the Fund or similar funds, please refer to http://apps.finra.org/fundanalyzer/1/fa.aspx.

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(The following financial statements of the Government Cash Management Portfolio should be read in conjunction with the Fund’s financial statements.)

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Investment Portfolio as of June 30, 2018 (Unaudited)

Government Cash Management Portfolio

	Principal Amount ($)		Value ($)
Government & Agency Obligations 91.6%
U.S. Government Sponsored Agencies 57.4%
Federal Farm Credit Bank:
1-month LIBOR minus 0.165%, 1.836%*, 11/2/2018		70,500,000		70,499,400
1-month LIBOR minus 0.165%, 1.881%*, 10/9/2018		37,500,000		37,499,454
1-month LIBOR minus 0.150%, 1.896%*, 10/11/2018		25,000,000		24,999,790
1-month LIBOR minus 0.135%, 1.911%*, 4/11/2019		150,000,000		150,000,000
1-month LIBOR minus 0.110%, 1.936%*, 3/12/2019		115,000,000		114,995,656
1-month LIBOR minus 0.145%, 1.949%*, 3/29/2019		166,000,000		166,000,000
1-month LIBOR minus 0.145%, 1.953%*, 2/26/2019		115,000,000		114,996,961
1-month LIBOR minus 0.130%, 1.964%*, 4/29/2019		246,500,000		246,500,000
1-month LIBOR minus 0.120%, 1.971%*, 3/25/2019		100,000,000		100,000,000
1-month LIBOR minus 0.070%, 1.976%*, 1/9/2019		50,000,000		50,000,000
1-month LIBOR minus 0.065%, 2.019%*, 7/20/2018		68,800,000		68,800,000
1-month LIBOR minus 0.003%, 2.133%*, 8/27/2018		75,000,000		74,999,088
3-month U.S. Treasury Bill Money Market Yield plus 0.280%, 2.189%*, 11/13/2018		60,000,000		60,000,000
3-month U.S. Treasury Bill Money Market Yield plus 0.300%, 2.209%*, 12/5/2018		50,000,000		50,000,000
Federal Home Loan Bank:
1.572%**, 7/2/2018		114,799,000		114,794,057
1-month LIBOR minus 0.160%, 1.822%*, 8/1/2018		200,000,000		200,000,000
1.825%**, 7/3/2018		115,500,000		115,488,450
1-month LIBOR minus 0.160%, 1.841%*, 8/3/2018		370,000,000		370,000,000
1.845%**, 7/24/2018		64,000,000		63,925,582
1-month LIBOR minus 0.155%, 1.85%*, 7/5/2018		205,000,000		205,000,000
1.86%**, 7/20/2018		75,000,000		74,927,364
1.86%**, 7/23/2018		75,000,000		74,915,896
1.87%**, 8/24/2018		78,000,000		77,784,252
1.873%**, 8/1/2018		100,000,000		99,840,953
1.88%**, 7/13/2018		286,500,000		286,322,943
1.881%**, 7/23/2018		343,250,000		342,860,888
1.886%**, 7/20/2018		800,000		799,215
1-month LIBOR minus 0.145%, 1.902%*, 8/13/2018		35,000,000		35,000,000
1-month LIBOR minus 0.090%, 1.915%*, 4/5/2019		88,000,000		88,000,000
1-month LIBOR minus 0.080%, 1.921%*, 2/4/2019		95,000,000		95,000,000
1-month LIBOR minus 0.090%, 1.923%*, 4/5/2019		150,000,000		150,000,000
1-month LIBOR minus 0.160%, 1.925%*, 7/19/2018		240,000,000		240,000,000
1-month LIBOR minus 0.130%, 1.927%*, 3/22/2019		233,250,000		233,250,000

The accompanying notes are an integral part of the financial statements.

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	Principal Amount ($)		Value ($)
1-month LIBOR minus 0.145%, 1.928%*, 8/15/2018		135,000,000		135,000,000
1-month LIBOR minus 0.150%, 1.935%*, 7/16/2018		188,000,000		188,000,000
1-month LIBOR minus 0.090%, 1.94%*, 11/8/2018		70,000,000		70,000,000
1.947%**, 9/4/2018		35,000,000		34,878,667
1-month LIBOR minus 0.135%, 1.95%*, 11/16/2018		190,000,000		190,000,000
1.951%**, 8/22/2018		585,000,000		583,374,220
1.957%**, 9/7/2018		595,000,000		592,830,894
1.957%**, 9/17/2018		25,000,000		24,895,458
1.957%**, 9/28/2018		95,000,000		94,546,715
1-month LIBOR minus 0.125%, 1.959%*, 8/20/2018		220,000,000		220,000,000
1-month LIBOR minus 0.130%, 1.961%*, 10/24/2018		120,000,000		120,000,000
1.962%**, 10/9/2018		25,000,000		24,865,625
1-month LIBOR minus 0.125%, 1.963%*, 6/21/2019		163,500,000		163,500,000
3-month LIBOR minus 0.390%, 1.965%*, 1/22/2019		5,125,000		5,125,000
1-month LIBOR minus 0.110%, 1.974%*, 2/22/2019		224,000,000		224,000,000
1-month LIBOR minus 0.120%, 1.978%*, 10/26/2018		300,000,000		300,000,000
1-month LIBOR minus 0.090%, 1.995%*, 1/18/2019		95,000,000		95,000,000
3-month LIBOR minus 0.330%, 2.005%*, 12/21/2018		155,000,000		155,000,000
1-month LIBOR minus 0.040%, 2.006%*, 7/9/2018		50,000,000		50,000,894
2.008%**, 10/25/2018		25,000,000		24,840,500
3-month LIBOR minus 0.310%, 2.017%*, 3/11/2019		210,000,000		210,000,000
1-month LIBOR minus 0.045%, 2.046%*, 1/24/2019		75,000,000		75,037,273
3-month LIBOR minus 0.250%, 2.058%*, 8/3/2018		168,000,000		168,000,000
2.069%**, 1/4/2019		607,000		600,565
3-month LIBOR minus 0.250%, 2.109%*, 7/30/2018		168,000,000		168,000,000
Federal Home Loan Mortgage Corp.:
0.875%, 10/12/2018		590,000		588,997
1.375%, 2/28/2019		906,000		901,684
1.749%**, 8/9/2018		50,000,000		49,906,562
1.774%**, 7/18/2018		200,000,000		199,834,721
1.779%**, 7/16/2018		56,000,000		55,959,050
1.784%**, 8/9/2018		22,000,000		21,958,053
1.815%**, 7/26/2018		220,000,000		219,726,528
1-month LIBOR minus 0.150%, 1.896%*, 2/12/2019		20,000,000		20,000,000
1.916%**, 8/20/2018		150,000,000		149,606,250
1-month LIBOR minus 0.16%, 1.925%*, 7/19/2018		150,000,000		150,000,000
1-month LIBOR minus 0.100%, 1.93%*, 8/8/2019		87,000,000		87,000,000
3-month LIBOR minus 0.280%, 2.073%*, 8/10/2018		100,000,000		100,000,000
3-month LIBOR minus 0.250%, 2.087%*, 10/10/2018		85,500,000		85,500,000
3-month LIBOR minus 0.250%, 2.109%*, 7/24/2018		965,000		964,962
				9,256,642,567

The accompanying notes are an integral part of the financial statements.

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	Principal Amount ($)		Value ($)
U.S. Treasury Obligations 34.2%
U.S. Treasury Bills:
1.257%**, 9/13/2018		5,000,000		4,987,255
1.832%**, 8/23/2018		300,000,000		299,202,019
1.855%**, 7/26/2018		475,000,000		474,396,353
1.86%**, 8/2/2018		200,000,000		199,673,778
1.872%**, 9/20/2018		155,000,000		154,356,207
1.886%**, 8/23/2018		16,000,000		15,956,187
1.906%**, 9/27/2018		300,000,000		298,621,334
1.916%**, 9/20/2018		125,000,000		124,468,437
1.918%**, 9/20/2018		125,000,000		124,467,875
1.921%**, 9/27/2018		366,000,000		364,304,607
1.924%**, 8/30/2018		120,000,000		119,620,400
1.977%**, 9/20/2018		280,000,000		278,771,500
2.008%**, 10/18/2018		200,000,000		198,801,000
2.009%**, 10/18/2018		85,000,000		84,490,168
2.058% **, 11/23/2018		200,000,000		198,364,722
2.059%**, 11/23/2018		108,500,000		107,612,643
U.S. Treasury Floating Rate Notes:
3-month U.S. Treasury Bill Money Market Yield plus 0.140%, 2.049%*, 1/31/2019		154,000,000		154,185,865
3-month U.S. Treasury Bill Money Market Yield plus 0.170%, 2.079%*, 10/31/2018		1,137,000,000		1,137,955,115
3-month U.S. Treasury Bill Money Market Yield plus 0.174%, 2.083%*, 7/31/2018		1,175,000,000		1,175,242,374
U.S. Treasury Notes, 0.75%, 9/30/2018		4,000,000		3,988,318
				5,519,466,157
Total Government & Agency Obligations (Cost $14,776,108,724)				14,776,108,724
Repurchase Agreements 8.3%
BNP Paribas, 2.1%, dated 6/29/2018, to be repurchased at $212,837,240 on 7/2/2018 (a)		212,800,000		212,800,000
Citigroup Global Markets, Inc., 2.1%, dated 6/29/2018, to be repurchased at $150,026,250 on 7/2/2018 (b)		150,000,000		150,000,000
Fixed Income Clearing Corp., 1.00%, dated 6/29/2018, to be repurchased at $300,025,000 on 7/2/2018 (c)		300,000,000		300,000,000
HSBC Securities, Inc., 2.11%, dated 6/29/2018, to be repurchased at $250,043,958 on 7/2/2018 (d)		250,000,000		250,000,000
Wells Fargo Bank, 2.12%, dated 6/29/2018, to be repurchased at $426,727,375 on 7/2/2018 (e)		426,652,000		426,652,000
Total Repurchase Agreements (Cost $1,339,452,000)				1,339,452,000

The accompanying notes are an integral part of the financial statements.

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	% of Net Assets		Value ($)
Total Investment Portfolio (Cost $16,115,560,724)		99.9		16,115,560,724
Other Assets and Liabilities, Net		0.1		15,655,398
Net Assets		100.0		16,131,216,122

* Floating rate security. These securities are shown at their current rate as of June 30, 2018.

** Annualized yield at time of purchase; not a coupon rate.

(a) Collateralized by:

Principal Amount ($)		Security	Rate (%)	Maturity Date		Collateral Value ($)
	95,982,500	U.S. Treasury Bonds	2.875–3.125		8/31/2022–5/31/2025		96,482,256
	106,451,100	U.S. Treasury Notes	1.25–2.875		5/15/2043–8/15/2045		107,109,770
	20,849,600	U.S. Treasury STRIPS	Zero Coupon		2/15/2033		13,464,046
	Total Collateral Value						217,056,072

(b) Collateralized by $158,000,000 U.S. Treasury Note, 1.75%, maturing on 03/31/2022 with a value of $153,000,009.

(c) Collateralized by $296,165,000 U.S. Treasury Notes, with the various coupon rates from 2.375–3.625%, with various maturity dates of 8/15/2020–2/15/2021 with a value of $306,003,436.

(d) Collateralized by $245,354,299 Government National Mortgage Association, with the various coupon rates from 3.5–5.5%, with various maturity dates of 11/20/2036–6/20/2048 with a value of $255,001,609.

(e) Collateralized by:

Principal Amount ($)		Security	Rate (%)	Maturity Date	Collateral Value ($)
	135,701,926	FREMF Mortgage Trust	0.1–3.703	11/25/2023–1/25/2046		1,262,614
	452,820	Federal Agricultural Mortgage Corp.	2.85	11/30/2021		455,314
	1,245,824	Federal Home Loan Bank	1.2–2.75	12/20/2018–6/10/2022		1,216,915
	99,000,958	Federal Home Loan Mortgage Corp.	2.00–6.50	11/1/2025–7/1/2048		99,205,939
	294,978,884	Federal National Mortgage Association	1.35–6.625	7/11/2018–8/1/2056		300,807,543
	284	Federal National Mortgage Association STRIPS	Zero Coupon	1/15/2028		207
	70,671,059	Federal National Mortgage Association- Interest Only	3.0–8.0	3/15/2029–8/25/2047		11,677,361
	55,956,981	Freddie Mac Multifamily Structured Pass-Through Certificates	0.815–2.896	3/25/2019–12/25/2041		3,294,853

The accompanying notes are an integral part of the financial statements.

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Principal Amount ($)		Security	Rate (%)	Maturity Date		Collateral Value ($)
	13,050,267	Government National Mortgage Association	2.5–10.00		2/20/2019–5/20/2048		12,796,118
	5,271,712	Tennessee Valley Authority	Zero Coupon–2.875		10/15/2018–9/15/2025		4,468,176
	Total Collateral Value						435,185,040

Interest Only: Interest Only (IO) bonds represent the “interest only” portion of payments on a pool of underlying mortgages or mortgage-backed securities. IO securities are subject to prepayment risk of the pool of underlying mortgages.

LIBOR: London Interbank Offered Rate

STRIPS: Separate Trading of Registered Interest and Principal Securities

Fair Value Measurements

Various inputs are used in determining the value of the Portfolio’s investments. These inputs are summarized in three broad levels. Level 1 includes quoted prices in active markets for identical securities. Level 2 includes other significant observable inputs (including quoted prices for similar securities, interest rates, prepayment speeds and credit risk). Level 3 includes significant unobservable inputs (including the Portfolio’s own assumptions in determining the fair value of investments). The level assigned to the securities valuations may not be an indication of the risk or liquidity associated with investing in those securities. Securities held by the Portfolio are reflected as Level 2 because the securities are valued at amortized cost (which approximates fair value) and, accordingly, the inputs used to determine value are not quoted prices in an active market.

The following is a summary of the inputs used as of June 30, 2018 in valuing the Portfolio’s investments. For information on the Portfolio’s policy regarding the valuation of investments, please refer to the Security Valuation section of Note A in the accompanying Notes to Financial Statements.

Assets	Level 1		Level 2		Level 3		Total
Investments in Securities (f)	$	—	$	14,776,108,724	$	—	$	14,776,108,724
Repurchase Agreements		—		1,339,452,000		—		1,339,452,000
Total	$	—	$	16,115,560,724	$	—	$	16,115,560,724

There have been no transfers between fair value measurement levels during the period ended June 30, 2018.

(f) See Investment Portfolio for additional detailed categorizations.

The accompanying notes are an integral part of the financial statements.

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Statement of Assets and Liabilities

as of June 30, 2018 (Unaudited)
Assets
Investments in non-affiliated securities, valued at amortized cost	$	16,115,560,724
Cash		89,877,991
Interest receivable		15,314,533
Other assets		416,468
Total assets		16,221,169,716
Liabilities
Payable for investment purchased		88,426,577
Accrued investment advisory fee		800,541
Accrued Trustees’ fees		59,032
Other accrued expenses and payables		667,444
Total liabilities		89,953,594
Net assets, at value	$	16,131,216,122

The accompanying notes are an integral part of the financial statements.

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Statement of Operations

for the six months ended June 30, 2018 (Unaudited)
Investment Income
Income:
Interest	$	152,505,763
Expenses:
Management fee		9,125,339
Administration fee		2,800,033
Custodian fee		72,562
Professional fees		140,158
Reports to shareholders		21,438
Trustees’ fees and expenses		523,492
Other		252,428
Total expenses before expense reductions		12,935,450
Expense reductions		(3,772,145	)
Total expenses after expense reductions		9,163,305
Net investment income		143,342,458
Net realized gain (loss) from investments		(30,111	)
Net increase (decrease) in net assets resulting from operations	$	143,312,347

The accompanying notes are an integral part of the financial statements.

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Statements of Changes in Net Assets

Increase (Decrease) in Net Assets	Six Months Ended June 30, 2018 (Unaudited)			Year Ended December 31, 2017
Operations:
Net investment income (loss)	$	143,342,458		$	106,771,143
Net realized gain (loss)		(30,111	)		338,378
Net increase (decrease) in net assets resulting from operations		143,312,347			107,109,521
Capital transactions in shares of beneficial interest:
Proceeds from capital invested		36,244,142,699			64,583,463,238
Value of capital withdrawn		(37,428,704,925	)		(59,493,039,509	)
Net increase (decrease) in net assets from capital transactions in shares of beneficial interest		(1,184,562,226	)		5,090,423,729
Increase (decrease) in net assets		(1,041,249,879	)		5,197,533,250
Net assets at beginning of period		17,172,466,001			11,974,932,751
Net assets at end of period	$	16,131,216,122		$	17,172,466,001

The accompanying notes are an integral part of the financial statements.

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Financial Highlights

	Six Months Ended 6/30/18			Years Ended December 31,
	(Unaudited)			2017		2016		2015		2014		2013
Ratios to Average Net Assets and Supplemental Data
Net assets, end of period ($ millions)		16,131			17,172		11,975		18,021		19,918		20,214
Ratio of expenses before expense reductions (%)		.14	*		.14		.16		.17		.17		.16
Ratio of expenses after expense reductions (%)		.10	*		.11		.11		.14		.14		.14
Ratio of net investment income (%)		1.54	*		.83		.32		.11		.05		.08
Total Return (%)a,b		.75	**		.81		.32		.11		.05		.08

^a Total return would have been lower had certain expenses not been reduced.

^b Total return for the Portfolio was derived from the performance of DWS Government Cash Reserves Fund Institutional.

^* Annualized

^** Not annualized

The accompanying notes are an integral part of the financial statements.

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Notes to Financial Statements (Unaudited)

A. Organization and Significant Accounting Policies

Government Cash Management Portfolio (the “Portfolio”) is registered under the Investment Company Act of 1940, as amended (the “1940 Act”), as an open-end management investment company organized as a New York trust.

The Portfolio is a master fund. A master/feeder fund structure is one in which a fund (a “feeder fund”), instead of investing directly in a portfolio of securities, invests most or all of its investment assets in a separate registered investment company (the “master fund”) with substantially the same investment objective and policies as the feeder fund. Such a structure permits the pooling of assets of two or more feeder funds, preserving separate identities or distribution channels at the feeder fund level. The Portfolio may have several feeder funds, including affiliated DWS feeder funds and unaffiliated feeder funds; with a significant ownership percentage of the Portfolio’s net assets. Investment activities of these feeder funds could have a material impact on the Portfolio. As of June 30, 2018, DWS Government Cash Management Fund, DWS Government Cash Reserves Fund Institutional and DWS Government Money Market Series owned approximately 11%, 2% and 84%, respectively, of the Portfolio.

The Portfolio’s financial statements are prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) which require the use of management estimates. Actual results could differ from those estimates. The Fund qualifies as an investment company under Topic 946 of Accounting Standards Codification of U.S. GAAP. The policies described below are followed consistently by the Portfolio in the preparation of its financial statements.

Security Valuation. Various inputs are used in determining the value of the Portfolio’s investments. These inputs are summarized in three broad levels. Level 1 includes quoted prices in active markets for identical securities. Level 2 includes other significant observable inputs (including quoted prices for similar securities, interest rates, prepayment speeds and credit risk). Level 3 includes significant unobservable inputs (including the Portfolio’s own assumptions in determining the fair value of investments). The level assigned to the securities valuations may not be an indication of the risk or liquidity associated with investing in those securities.

The Portfolio values all securities utilizing the amortized cost method permitted in accordance with Rule 2a-7 under the 1940 Act and certain conditions therein. Under this method, which does not take into account unrealized capital gains or losses on securities, an instrument is initially

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valued at its cost and thereafter assumes a constant accretion/amortization rate to maturity of any discount or premium. Securities held by the Portfolio are reflected as Level 2 because the securities are valued at amortized cost (which approximates fair value) and, accordingly, the inputs used to determine value are not quoted prices in an active market.

Repurchase Agreements. The Portfolio may enter into repurchase agreements, under the terms of a Master Repurchase Agreement, with certain banks and broker/dealers whereby the Portfolio, through its custodian or a sub-custodian bank, receives delivery of the underlying securities, the amount of which at the time of purchase and each subsequent business day is required to be maintained at such a level that the value is equal to at least the principal amount of the repurchase price plus accrued interest. The custodian bank or another designated subcustodian holds the collateral in a separate account until the agreement matures. If the value of the securities falls below the principal amount of the repurchase agreement plus accrued interest, the financial institution deposits additional collateral by the following business day. If the financial institution either fails to deposit the required additional collateral or fails to repurchase the securities as agreed, the Portfolio has the right to sell the securities and recover any resulting loss from the financial institution. If the financial institution enters into bankruptcy, the Portfolio’s claims on the collateral may be subject to legal proceedings.

As of June 30, 2018, the Portfolio held repurchase agreements with a gross value of $1,339,452,000. The value of the related collateral exceeded the value of the repurchase agreements at period end. The detail of the related collateral is included in the footnotes following the Portfolio’s Investment Portfolio.

Federal Income Taxes. The Portfolio is considered a Partnership under the Internal Revenue Code, as amended. Therefore, no federal income tax provision is necessary.

It is intended that the Portfolio’s assets, income and distributions will be managed in such a way that an investor in the Portfolio will be able to satisfy the requirements of Subchapter M of the Code, assuming that the investor invested all of its assets in the Portfolio.

At December 31, 2017, Government Cash Management Portfolio had an aggregate cost of investments for federal income tax purposes of $17,453,872,167.

The Portfolio has reviewed the tax positions for the open tax years as of December 31, 2017 and has determined that no provision for income tax and/or uncertain tax provisions is required in the Portfolio’s financial statements. The Portfolio’s federal tax returns for the prior three fiscal years remain open subject to examination by the Internal Revenue Service.

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Contingencies. In the normal course of business, the Portfolio may enter into contracts with service providers that contain general indemnification clauses. The Portfolio’s maximum exposure under these arrangements is unknown, as this would involve future claims that may be made against the Portfolio that have not yet been made. However, based on experience, the Portfolio expects the risk of loss to be remote.

Other. Investment transactions are accounted for on trade date. Interest income is recorded on the accrual basis. Realized gains and losses from investment transactions are recorded on an identified cost basis. All discounts and premiums are accreted/amortized for both tax and financial reporting purposes.

The Portfolio makes an allocation of its net investment income and realized gains and losses from securities transactions to its investors in proportion to their investment in the Portfolio.

B. Fees and Transactions with Affiliates

Management Agreement. Under the Investment Management Agreement with DWS Investment Management Americas, Inc. (formerly Deutsche Investment Management Americas Inc.) (“DIMA” or the “Advisor”), an indirect, wholly owned subsidiary of DWS Group GmbH & Co. KGaA (“DWS Group”), the Advisor determines the securities, instruments and other contracts relating to investments to be purchased, sold or entered into by the Portfolio.

Under the Investment Management Agreement, the Portfolio pays the Advisor a monthly management fee based on its average daily net assets, computed and accrued daily and payable monthly, at the following annual rates:

First $3.0 billion of the Portfolio’s average daily net assets	.1200%
Next $4.5 billion of such net assets	.1025%
Over $7.5 billion of such net assets	.0900%

Accordingly, for the six months ended June 30, 2018, the fee pursuant to the Investment Management Agreement was equivalent to an annualized rate (exclusive of any applicable waivers/reimbursements) of 0.10% of the Fund’s average daily net assets.

For the period from January 1, 2018 through September 30, 2018, the Advisor has contractually agreed to waive its fees and/or reimburse certain operating expenses to the extent necessary to maintain the total annual operating expenses (excluding certain expenses such as extraordinary expenses, taxes, brokerage and interest) at 0.14% of the Portfolio’s average daily net assets.

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For the period from January 1, 2018 through April 10, 2018, the Advisor had voluntarily agreed to waive its fees and/or reimburse certain operating expenses to the extent necessary to maintain the total annual operating expenses (excluding certain expenses such as extraordinary expenses, taxes, brokerage and interest) at 0.10% of the Portfolio’s average daily net assets.

For the period from April 11, 2018 through April 26, 2018, the Advisor had voluntarily agreed to waive its fees and/or reimburse certain operating expenses to the extent necessary to maintain the total annual operating expenses (excluding certain expenses such as extraordinary expenses, taxes, brokerage and interest) at 0.08% of the Portfolio’s average daily net assets.

Effective April 27, 2018 through June 30, 2018, the Advisor has voluntarily agreed to waive its fees and/or reimburse certain operating expenses to the extent necessary to maintain the total annual operating expenses (excluding certain expenses such as extraordinary expenses, taxes, brokerage and interest) at 0.10% of the Portfolio’s average daily net assets. This voluntary waiver or reimbursement may be terminated at any time at the option of the Advisor.

For the six months ended June 30, 2018, fees waived and/or expenses reimbursed are $3,772,145.

Administration Fee. Pursuant to an Administrative Services Agreement, DIMA provides most administrative services to the Portfolio. For all services provided under the Administrative Services Agreement, the Portfolio pays the Advisor an annual fee (“Administration Fee”) of 0.03% of the Portfolio’s average daily net assets, computed and accrued daily and payable monthly. For the six months ended June 30, 2018, the Administration Fee was $2,800,033, of which $491,191 is unpaid.

Filing Service Fees. Under an agreement with DIMA, DIMA is compensated for providing certain regulatory filing services to the Portfolio. For the six months ended June 30, 2018, the amount charged to the Portfolio by DIMA included in the Statement of Operations under “Reports to shareholders” aggregated $751, all of which is unpaid.

Trustees’ Fees and Expenses. The Portfolio paid retainer fees to each Trustee not affiliated with the Advisor, plus specified amounts to the Board Chairperson and Vice Chairperson and to each committee Chairperson.

C. Line of Credit

The Portfolio and other affiliated funds (the “Participants”) share in a $400 million revolving credit facility provided by a syndication of banks. The Portfolio may borrow for temporary or emergency purposes, including the meeting of redemption requests that otherwise might require the

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untimely disposition of securities. The Participants are charged an annual commitment fee which is allocated based on net assets, among each of the Participants. Interest is calculated at a rate per annum equal to the sum of the Federal Funds Rate plus 1.25 percent plus if the one-month LIBOR exceeds the Federal Funds Rate, the amount of such excess. The Portfolio may borrow up to a maximum of 33 percent of its net assets under the agreement. The Portfolio had no outstanding loans at June 30, 2018.

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Advisory Agreement Board Considerations and Fee Evaluation

Deutsche Government Cash Reserves Fund Institutional (now known as DWS Government Cash Reserves Fund Institutional) (the “Fund”), a series of Deutsche Money Market Trust (now known as Deutsche DWS Money Market Trust), invests substantially all of its assets in Government Cash Management Portfolio (the “Portfolio”) in order to achieve its investment objective. The Portfolio’s Board of Trustees approved the renewal of the Portfolio’s investment management agreement (the “Portfolio Agreement”) with Deutsche Investment Management Americas Inc. (now known as DWS Investment Management Americas, Inc.) (“DIMA”) and the Fund’s Board of Trustees (which consists of the same members as the Board of Trustees of the Portfolio) approved the renewal of the Fund’s investment management agreement with DIMA (the “Fund Agreement,” and together with the Portfolio Agreement, the “Agreements”) in September 2017. The Portfolio’s Board of Trustees and the Fund’s Board of Trustees are collectively referred to as the “Board” or “Trustees.”

In terms of the process that the Board followed prior to approving the Agreements, shareholders should know that:

– During the entire process, all of the Portfolio’s and the Fund’s Trustees were independent of DIMA and its affiliates (the “Independent Trustees”).

– The Board met frequently during the past year to discuss fund matters and dedicated a substantial amount of time to contract review matters. Over the course of several months, the Board’s Contract Committee reviewed extensive materials received from DIMA, independent third parties and independent counsel. These materials included an analysis of performance, fees and expenses, and profitability from a fee consultant retained by the Independent Trustees (the “Fee Consultant”). Based on its evaluation of the information provided, the Contract Committee presented its findings and recommendations to the Board. The Board then reviewed the Contract Committee’s findings and recommendations.

– The Board also received extensive information throughout the year regarding performance of the Portfolio and the Fund.

– The Independent Trustees regularly met privately with counsel to discuss contract review and other matters. In addition, the Independent Trustees were advised by the Fee Consultant in the course of their review of the Portfolio’s and the Fund’s contractual arrangements and considered a comprehensive report prepared by the Fee Consultant in connection with their deliberations.

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– In connection with reviewing the Agreements, the Board also reviewed the terms of the Fund’s distribution agreement, administrative services agreement, transfer agency agreement and other material service agreements.

In connection with the contract review process, the Contract Committee and the Board considered the factors discussed below, among others. The Board also considered that DIMA and its predecessors have managed the Portfolio and the Fund since their inception, and the Board believes that a long-term relationship with a capable, conscientious advisor is in the best interests of the Portfolio and the Fund. The Board considered, generally, that shareholders chose to invest or remain invested in the Fund knowing that DIMA managed the Portfolio and the Fund. DIMA is part of Deutsche Bank AG’s (“Deutsche Bank”) Asset Management (“Deutsche AM”) division. Deutsche AM is a global asset management business that offers a wide range of investing expertise and resources, including research capabilities in many countries throughout the world.

As part of the contract review process, the Board carefully considered the fees and expenses of each Deutsche fund overseen by the Board in light of the fund’s performance. In many cases, this led to the negotiation and implementation of expense caps. As part of these negotiations, the Board indicated that it would consider relaxing these caps in future years following sustained improvements in performance, among other considerations.

While shareholders may focus primarily on fund performance and fees, the Board considers these and many other factors, including the quality and integrity of DIMA’s personnel and administrative support services provided by DIMA, such as back-office operations, fund valuations, and compliance policies and procedures.

Nature, Quality and Extent of Services. The Board considered the terms of the Agreements, including the scope of advisory services provided under the Agreements. The Board noted that, under the Agreements, DIMA provides portfolio management services to the Portfolio and the Fund and that, pursuant to separate administrative services agreements, DIMA provides administrative services to the Portfolio and the Fund. The Board considered the experience and skills of senior management and investment personnel and the resources made available to such personnel. The Board reviewed the Portfolio’s and the Fund’s performance over short-term and long-term periods and compared those returns to various agreed-upon performance measures, including a peer universe compiled using information supplied by iMoneyNet, an independent fund data service. The Board also noted that it has put into place a process of identifying “Funds in Review” (e.g., funds performing poorly relative to a peer universe), and receives additional reporting from

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DIMA regarding such funds and, where appropriate, DIMA’s plans to address underperformance. The Board believes this process is an effective manner of identifying and addressing underperforming funds. Based on the information provided, the Board noted that, for the one- and three-year periods ended December 31, 2016, the Fund’s gross performance (Institutional Class shares) was in the 2nd quartile and 1st quartile, respectively, of the applicable iMoneyNet universe (the 1st quartile being the best performers and the 4th quartile being the worst performers).

Fees and Expenses. The Board considered the Portfolio’s and the Fund’s investment management fee schedules, the Fund’s operating expenses and total expense ratios, and comparative information provided by Broadridge Financial Solutions, Inc. (“Broadridge”) and the Fee Consultant regarding investment management fee rates paid to other investment advisors by similar funds (1st quartile being the most favorable and 4th quartile being the least favorable). With respect to management fees paid to other investment advisors by similar funds, the Board noted that the contractual fee rates paid by the Portfolio and the Fund, which include 0.03% and 0.10% fees paid to DIMA under the respective administrative services agreements, were higher than the median (3rd quartile) of the applicable Broadridge peer group (based on Broadridge data provided as of December 31, 2016). The Board noted that, although shareholders of the Fund indirectly bear the Portfolio’s management fee, the Fund does not charge an additional investment management fee. Based on Broadridge data provided as of December 31, 2016, the Board noted that the Fund’s total (net) operating expenses, which include Portfolio expenses allocated to the Fund, were higher than the median of the applicable Broadridge expense universe for Institutional Class shares (3rd quartile). The Board noted the expense limitation agreed to by DIMA. The Board also noted the voluntary fee waivers implemented by DIMA to ensure the Fund maintained a positive yield. The Board considered the management fee rate as compared to fees charged by DIMA to comparable Deutsche U.S. registered funds (“Deutsche Funds”) and considered differences between the Portfolio and the Fund and the comparable Deutsche Funds. The information requested by the Board as part of its review of fees and expenses also included information about institutional accounts (including any sub-advised funds and accounts) and funds offered primarily to European investors (“Deutsche Europe funds”) managed by Deutsche AM. The Board noted that DIMA indicated that Deutsche AM does not manage any institutional accounts or Deutsche Europe funds comparable to the Portfolio and the Fund. The Board considered that the Portfolio’s management fee was reduced by 0.03% at all breakpoint levels in connection with the restructuring of the Portfolio and the Fund into government money market funds in 2016.

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On the basis of the information provided, the Board concluded that management fees were reasonable and appropriate in light of the nature, quality and extent of services provided by DIMA.

Profitability. The Board reviewed detailed information regarding revenues received by DIMA under the Agreements. The Board considered the estimated costs to DIMA, and pre-tax profits realized by DIMA, from advising the Deutsche Funds, as well as estimates of the pre-tax profits attributable to managing the Fund in particular. The Board also received information regarding the estimated enterprise-wide profitability of DIMA and its affiliates with respect to all fund services in totality and by fund. The Board and the Fee Consultant reviewed DIMA’s methodology in allocating its costs to the management of the Fund. Based on the information provided, the Board concluded that the pre-tax profits realized by DIMA in connection with the management of the Fund were not unreasonable. The Board also reviewed certain publicly available information regarding the profitability of certain similar investment management firms. The Board noted that, while information regarding the profitability of such firms is limited (and in some cases is not necessarily prepared on a comparable basis), DIMA and its affiliates’ overall profitability with respect to the Deutsche Funds (after taking into account distribution and other services provided to the funds by DIMA and its affiliates) was lower than the overall profitability levels of most comparable firms for which such data was available.

Economies of Scale. The Board considered whether there are economies of scale with respect to the management of the Portfolio and the Fund and whether the Portfolio and the Fund benefit from any economies of scale. The Board noted that the Portfolio’s and the Fund’s investment management fee schedule includes fee breakpoints. The Board concluded that the Portfolio’s and the Fund’s fee schedule represents an appropriate sharing between the Portfolio and the Fund and DIMA of such economies of scale as may exist in the management of the Portfolio and the Fund at current asset levels.

Other Benefits to DIMA and Its Affiliates. The Board also considered the character and amount of other incidental benefits received by DIMA and its affiliates, including any fees received by DIMA for administrative services provided to the Portfolio and the Fund and any fees received by an affiliate of DIMA for transfer agency services provided to the Fund. The Board also considered benefits to DIMA related to brokerage and soft-dollar allocations, including allocating brokerage to pay for research generated by parties other than the executing broker dealers, which pertain primarily to funds investing in equity securities. In addition, the Board considered the incidental public relations benefits to DIMA related to Deutsche Funds advertising and cross-selling opportunities among

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DIMA products and services. The Board considered these benefits in reaching its conclusion that the Portfolio’s and the Fund’s management fees were reasonable.

Compliance. The Board considered the significant attention and resources dedicated by DIMA to documenting and enhancing its compliance processes in recent years. The Board noted in particular (i) the experience, seniority and time commitment of the individuals serving as DIMA’s and the Fund’s chief compliance officers; (ii) the large number of DIMA compliance personnel; and (iii) the substantial commitment of resources by DIMA and its affiliates to compliance matters.

Based on all of the information considered and the conclusions reached, the Board unanimously determined that the continuation of the Agreements is in the best interests of the Portfolio and the Fund. In making this determination, the Board did not give particular weight to any single factor identified above. The Board considered these factors over the course of numerous meetings, certain of which were in executive session with only the Independent Trustees and counsel present. It is possible that individual Independent Trustees may have weighed these factors differently in reaching their individual decisions to approve the continuation of the Agreements.

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Account Management Resources

Automated Information Line	Institutional Investor Services (800) 730-1313 Personalized account information, information on other DWS funds and services via touchtone telephone and the ability to exchange or redeem shares.
Web Site	liquidity.dws.com View your account transactions and balances, trade shares, monitor your asset allocation, subscribe to fund and account updates by e-mail, and change your address, 24 hours a day. Obtain prospectuses and applications, news about DWS funds, insight from DWS economists and investment specialists and access to DWS fund account information.
For More Information	(800) 730-1313, option 1 To speak with a fund service representative.
Written Correspondence	DWS PO Box 219210 Kansas City, MO 64121-9210
Proxy Voting	The Fund’s policies and procedures for voting proxies for portfolio securities and information about how the Fund voted proxies related to its portfolio securities during the most recent 12-month period ended June 30 are available on our Web site — dws.com/en-us/resources/proxy-voting — or on the SEC’s Web site — sec.gov. To obtain a written copy of the Fund’s policies and procedures without charge, upon request, call us toll free at (800) 728-3337.
Portfolio Holdings	Following the Fund’s fiscal first and third quarter-end, a complete portfolio holdings listing is filed with the SEC on Form N-Q. In addition, each month, information about the Fund and its portfolio holdings is filed with the SEC on Form N-MFP. The SEC delays the public availability of the information filed on Form N-MFP for 60 days after the end of the reporting period included in the filing. These forms will be available on the SEC’s Web site at sec.gov, and they may also be reviewed and copied at the SEC’s Public Reference Room in Washington, D.C. Information on the operation of the SEC’s Public Reference Room may be obtained by calling (800) SEC-0330. The Fund’s portfolio holdings are also posted on dws.com from time to time. Please see the Fund’s current prospectus for more information.
Principal Underwriter	If you have questions, comments or complaints, contact: DWS Distributors, Inc. 222 South Riverside Plaza Chicago, IL 60606-5808 (800) 621-1148

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Investment Management	DWS Investment Management Americas, Inc. (“DIMA” or the “Advisor”), which is part of the DWS Group GmbH & Co. KGaA (“DWS Group”), is the investment advisor for the Fund. DIMA and its predecessors have more than 90 years of experience managing mutual funds and DIMA provides a full range of investment advisory services to both institutional and retail clients. DIMA is an indirect, wholly owned subsidiary of DWS Group. DWS Group is a global organization that offers a wide range of investing expertise and resources, including hundreds of portfolio managers and analysts and an office network that reaches the world’s major investment centers. This well-resourced global investment platform brings together a wide variety of experience and investment insight across industries, regions, asset classes and investing styles.
Nasdaq Symbol	BIRXX
CUSIP Number	25160K 405
Fund Number	500

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Privacy Statement

FACTS	What Does DWS Do With Your Personal Information?
Why?	Financial companies choose how they share your personal information. Federal law gives consumers the right to limit some but not all sharing. Federal law also requires us to tell you how we collect, share and protect your personal information. Please read this notice carefully to understand what we do.
What?	The types of personal information we collect and share can include: – Social Security number – Account balances – Purchase and transaction history – Bank account information – Contact information such as mailing address, e-mail address and telephone number
How?	All financial companies need to share customers’ personal information to run their everyday business. In the section below, we list the reasons financial companies can share their customers’ personal information, the reasons DWS chooses to share and whether you can limit this sharing.

Reasons we can share your personal information	Does DWS share?	Can you limit this sharing?
For our everyday business purposes — such as to process your transactions, maintain your account(s), respond to court orders or legal investigations	Yes	No
For our marketing purposes — to offer our products and services to you	Yes	No
For joint marketing with other financial companies	No	We do not share
For our affiliates’ everyday business purposes — information about your transactions and experiences	No	We do not share
For our affiliates’ everyday business purposes — information about your creditworthiness	No	We do not share
For non-affiliates to market to you	No	We do not share

Questions? Call (800) 728-3337 or e-mail us at service@dws.com

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Who we are
Who is providing this notice?	DWS Distributors, Inc; DWS Investment Management Americas, Inc.; DWS Trust Company; the DWS Funds
What we do
How does DWS protect my personal information?	To protect your personal information from unauthorized access and use, we use security measures that comply with federal law. These measures include computer safeguards and secured files and buildings.
How does DWS collect my personal information?	We collect your personal information, for example, when you: – open an account – give us your contact information – provide bank account information for ACH or wire transactions – tell us where to send money – seek advice about your investments
Why can’t I limit all sharing?	Federal law gives you the right to limit only – sharing for affiliates’ everyday business purposes – information about your creditworthiness – affiliates from using your information to market to you – sharing for non-affiliates to market to you State laws and individual companies may give you additional rights to limit sharing.
Definitions
Affiliates	Companies related by common ownership or control. They can be financial or non-financial companies. Our affiliates include financial companies with the DWS or Deutsche Bank (“DB”) name, such as DB AG Frankfurt.
Non-affiliates	Companies not related by common ownership or control. They can be financial and non-financial companies. Non-affiliates we share with include account service providers, service quality monitoring services, mailing service providers and verification services to help in the fight against money laundering and fraud.
Joint marketing	A formal agreement between non-affiliated financial companies that together market financial products or services to you. DWS does not jointly market.

Rev. 3/2018, as amended 7/2018

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Notes

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Notes

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DGCRF-3

(R-028297-7 8/18)

Table of Contents

June 30, 2018

Semiannual Report

to Shareholders

DWS Government Cash Management Fund

(formerly Deutsche Government Cash Management Fund)

Table of Contents

Contents

DWS Government Cash Management Fund
3	Portfolio Summary
4	Statement of Assets and Liabilities
5	Statement of Operations
6	Statements of Changes in Net Assets
7	Financial Highlights
8	Notes to Financial Statements
12	Information About Your Fund’s Expenses
Government Cash Management Portfolio
15	Investment Portfolio
20	Statement of Assets and Liabilities
21	Statement of Operations
22	Statements of Changes in Net Assets
23	Financial Highlights
24	Notes to Financial Statements
29	Advisory Agreement Board Considerations and Fee Evaluation
34	Account Management Resources
36	Privacy Statement

This report must be preceded or accompanied by a prospectus. To obtain a summary prospectus, if available, or prospectus for any of our funds, refer to the Account Management Resources information provided in the back of this booklet. We advise you to consider the Fund’s objectives, risks, charges and expenses carefully before investing. The summary prospectus and prospectus contain this and other important information about the Fund. Please read the prospectus carefully before you invest.

You could lose money by investing in the Fund. Although the Fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so. An investment in the Fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The Fund’s sponsor has no legal obligation to provide financial support to the Fund, and you should not expect that the sponsor will provide financial support to the Fund at any time. You should not rely on or expect the Advisor to enter into support agreements or take other actions to maintain the Fund’s $1.00 share price. The credit quality of the Fund’s holdings can change rapidly in certain markets, and the default of a single holding could have an adverse impact on the Fund’s share price. The Fund’s share price can also be negatively affected during periods of high redemption pressures and/or illiquid markets. The actions of a few large investors of the Fund may have a significant adverse effect on the share price of the Fund. Please read the prospectus for specific details regarding the Fund’s risk profile.

The brand DWS represents DWS Group GmbH & Co. KGaA and any of its subsidiaries such as DWS Distributors, Inc. which offers investment products or DWS Investment Management Americas, Inc. and RREEF America L.L.C. which offer advisory services.

NOT FDIC/NCUA INSURED     NO BANK GUARANTEE     MAY LOSE VALUE NOT A DEPOSIT     NOT INSURED BY ANY FEDERAL GOVERNMENT AGENCY

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Portfolio Summary		(Unaudited)
Asset Allocation (As a % of Investment Portfolio)	6/30/18		12/31/17
Government & Agency Obligations		92%		90%
Repurchase Agreements		8%		10%
		100%		100%
Weighted Average Maturity	6/30/18		12/31/17
DWS Government Cash Management Fund		32 days		43 days
Government & Agency Institutional*		29 days		31 days

* The Fund is compared to its respective iMoneyNet category: Government & Agency Institutional — Category includes the most broadly based of the government institutional funds. These funds may invest in U.S. Treasury securities, securities issued or guaranteed by the U.S. Government or its agencies or instrumentalities.

Weighted average maturity, also known as effective maturity, is the weighted average of the maturity date of bonds held by the Fund taking into consideration any available maturity shortening features.

Portfolio holdings and characteristics are subject to change.

For more complete details about the portfolio’s holdings, see page 15. A quarterly Fact Sheet is available on liquidity.dws.com/US/products/fund_facts_prospectus_l2.jsp or upon request. Please see the Account Management Resources section on page 34 for contact information.

DWS Government Cash Management Fund | 3

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Statement of Assets and Liabilities

as of June 30, 2018 (Unaudited)
Assets
Investment in Government Cash Management Portfolio, at value	$	1,763,133,675
Receivable for Fund shares sold		262
Other assets		12,641
Total assets		1,763,146,578
Liabilities
Payable for Fund shares redeemed		18
Distributions payable		224,098
Accrued Trustees’ fees		438
Other accrued expenses and payables		444,184
Total liabilities		668,738
Net assets, at value	$	1,762,477,840
Net Assets Consist of
Distributions in excess of net investment income		(121	)
Accumulated net realized gain (loss)		32,934
Paid-in capital		1,762,445,027
Net assets, at value	$	1,762,477,840
Net Asset Value
Institutional Shares
Net Asset Value, offering and redemption price per share ($1,762,477,840 ÷ 1,762,539,886 outstanding shares of beneficial interest, $.01 par value, unlimited number of shares authorized)	$	1.00

The accompanying notes are an integral part of the financial statements.

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Statement of Operations

for the six months ended June 30, 2018 (Unaudited)
Investment Income
Income and expenses allocated from Government Cash Management Portfolio:
Interest	$	14,672,191
Expenses*		(875,093	)
Net investment income allocated from Government Cash Management Portfolio		13,797,098
Expenses:
Administration fee		890,733
Services to shareholders		35,503
Service fees		548,876
Professional fees		20,557
Reports to shareholders		9,890
Registration fees		11,894
Trustees’ fees and expenses		2,383
Other		19,405
Total expenses		1,539,241
Net investment income		12,257,857
Net realized gain (loss) allocated from Government Cash Management Portfolio		(4,201	)
Net increase (decrease) in net assets resulting from operations	$	12,253,656

* Net of $362,639 Advisor reimbursement allocated from Government Cash Management Portfolio for the six months ended June 30, 2018.

The accompanying notes are an integral part of the financial statements.

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Statements of Changes in Net Assets

	Six Months Ended June 30, 2018 (Unaudited)			Year Ended December 31, 2017
Increase (Decrease) in Net Assets
Operations:
Net investment income	$	12,257,857		$	9,702,081
Net realized gain (loss)		(4,201	)		37,135
Net increase (decrease) in net assets resulting from operations		12,253,656			9,739,216
Distributions to shareholders from:
Net investment income		(12,261,061	)		(9,700,252	)
Fund share transactions:
Proceeds from shares sold		2,218,916,310			3,685,868,695
Reinvestment of distributions		11,329,863			8,780,803
Payments for shares redeemed		(2,150,204,706	)		(4,001,787,613	)
Net increase (decrease) in net assets from Fund share transactions		80,041,467			(307,138,115	)
Increase (decrease) in net assets		80,034,062			(307,099,151	)
Net assets at beginning of period		1,682,443,778			1,989,542,929
Net assets at end of period (including distributions in excess of net investment income and undistributed net investment income of $121 and $3,083, respectively)	$	1,762,477,840		$	1,682,443,778
Other Information:
Shares outstanding at beginning of period		1,682,498,419			1,989,636,534
Shares sold		2,218,916,310			3,685,868,695
Shares issued to shareholders in reinvestment of distributions		11,329,863			8,780,803
Shares redeemed		(2,150,204,706	)		(4,001,787,613	)
Net increase (decrease) in Fund shares		80,041,467			(307,138,115	)
Shares outstanding at end of period		1,762,539,886			1,682,498,419

The accompanying notes are an integral part of the financial statements.

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Financial Highlights

Institutional Shares	Six Months Ended 6/30/18				Years Ended December 31,
	(Unaudited)				2017			2016			2015			2014			2013
Selected Per Share Data
Net asset value, beginning of period		$	1.00		$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Income from investment operations:
Net investment income			.007			.006			.002			.000	***		.000	***		.000	***
Net realized gain (loss)			(.000	)***		.000	***		.000	***		.000	***		.000	***		.000	***
Total from investment operations			.007			.006			.002			.000	***		.000	***		.000	***
Less distributions from:
Net investment income			(.007	)		(.006	)		(.002	)		(.000	)***		(.000	)***		(.000	)***
Net asset value, end of period		$	1.00		$	1.00		$	1.00		$	1.00		$	1.00		$	1.00
Total Return (%)a			.67	**		.64			.16			.01			.01			.01
Ratios to Average Net Assets and Supplemental Data
Net assets, end of period ($ millions)			1,762			1,682			1,990			2,202			911			1,536
Ratio of expenses before expense reductions, including expenses allocated from Government Cash Management Portfolio (%)			.31	*		.32			.32			.34			.34			.33
Ratio of expenses after expense reductions, including expenses allocated from Government Cash Management Portfolio (%)			.27	*		.28			.27			.24			.18			.21
Ratio of net investment income (%)			1.38	*		.63			.16			.02			.01			.01

^a Total return would have been lower had certain expenses not been reduced.

^* Annualized

^** Not annualized

^*** Amount is less than $.0005.

The accompanying notes are an integral part of the financial statements.

DWS Government Cash Management Fund | 7

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Notes to Financial Statements (Unaudited)

A. Organization and Significant Accounting Policies

DWS Government Cash Management Fund (formerly Deutsche Government Cash Management Fund) (the “Fund”) is a diversified series of Deutsche DWS Money Market Trust (formerly Deutsche Money Market Trust) (the “Trust”), which is registered under the Investment Company Act of 1940, as amended (the “1940 Act”), as an open-end management investment company organized as a Massachusetts business trust. The Fund currently offers one class of shares, Institutional Shares, to investors.

The Fund is a feeder fund that seeks to achieve its investment objective by investing substantially all of its investable assets in a master portfolio, the Government Cash Management Portfolio (the “Portfolio”), an open-end management investment company registered under the 1940 Act and organized as a New York trust advised by DWS Investment Management Americas, Inc. (formerly Deutsche Investment Management Americas Inc.) (“DIMA” or the “Advisor”), an indirect, wholly owned subsidiary of DWS Group GmbH & Co. KGaA (“DWS Group”). A master/feeder fund structure is one in which a fund (a “feeder fund”), instead of investing directly in a portfolio of securities, invests most or all of its investment assets in a separate registered investment company (the “master fund”) with substantially the same investment objective and policies as the feeder fund. Such a structure permits the pooling of assets of two or more feeder funds, preserving separate identities or distribution channels at the feeder fund level. At June 30, 2018, the Fund owned approximately 11% of the Portfolio.

The Fund’s financial statements are prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) which require the use of management estimates. Actual results could differ from those estimates. The Fund qualifies as an investment company under Topic 946 of Accounting Standards Codification of U.S. GAAP. The policies described below are followed consistently by the Fund in the preparation of its financial statements. The financial statements of the Portfolio, including the Investment Portfolio, are contained elsewhere in this report and should be read in conjunction with the Fund’s financial statements.

Security Valuation. The Fund records its investment in the Portfolio at value, which reflects its proportionate interest in the net assets of the Portfolio and is categorized as Level 1. Valuation of the securities held by the Portfolio is discussed in the notes to the Portfolio’s financial statements included elsewhere in this report.

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Disclosure about the classification of fair value measurements is included in a table following the Portfolio’s Investment Portfolio.

Federal Income Taxes. The Fund’s policy is to comply with the requirements of the Internal Revenue Code, as amended, which are applicable to regulated investment companies, and to distribute all of its taxable income to its shareholders.

The Fund has reviewed the tax positions for the open tax years as of December 31, 2017 and has determined that no provision for income tax and/or uncertain tax provisions is required in the Fund’s financial statements. The Fund’s federal tax returns for the prior three fiscal years remain open subject to examination by the Internal Revenue Service.

Distribution of Income and Gains. Net investment income of the Fund is declared as a daily dividend and is distributed to shareholders monthly. The Fund may take into account capital gains and losses in its daily dividend declarations. The Fund may also make additional distributions for tax purposes if necessary.

Permanent book and tax differences relating to shareholder distributions will result in reclassifications to paid in capital. Temporary book and tax differences will reverse in a subsequent period. There were no significant book to tax differences for the Fund.

The tax character of current year distributions will be determined at the end of the current fiscal year.

Contingencies. In the normal course of business, the Fund may enter into contracts with service providers that contain general indemnification clauses. The Fund’s maximum exposure under these arrangements is unknown, as this would involve future claims that may be made against the Fund that have not yet been made. However, based on experience, the Fund expects the risk of loss to be remote.

Other. The Fund receives an allocation of the Portfolio’s net investment income and net realized gains and losses in proportion to its investment in the Portfolio. Expenses directly attributed to a fund are charged to that fund, while expenses which are attributable to the Trust are allocated among the funds in the Trust on the basis of relative net assets.

B. Fees and Transactions with Affiliates

Management Agreement. Under the Investment Management Agreement with DWS Investment Management Americas, Inc. (formerly

Deutsche Investment Management Americas Inc.) (“DIMA” or the “Advisor”), an indirect, wholly owned subsidiary of DWS Group GmbH & Co. KGaA (“DWS Group”), the Advisor serves as the investment manager to the Fund. The Advisor receives a management fee from the Portfolio pursuant to the master/feeder structure listed above in Note A.

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For the period from January 1, 2018 through April 30, 2019, DIMA has contractually agreed to waive its fees and/or reimburse certain operating expenses of the Fund, including expenses of the Portfolio allocated to the Fund, to the extent necessary to maintain the total annual operating expenses (excluding certain expenses such as extraordinary expenses, taxes, brokerage and interest) at 0.30% of the Fund’s average daily net assets.

Administration Fee. Pursuant to an Administrative Services Agreement, DIMA provides most administrative services to the Fund. For all services provided under the Administrative Services Agreement, the Fund pays the Advisor an annual fee (“Administration Fee”) of 0.10% of the Fund’s average daily net assets, computed and accrued daily and payable monthly. For the six months ended June 30, 2018, the Administration Fee was $890,733, of which $177,987 is unpaid.

Service Provider Fees. DWS Service Company (“DSC”), an affiliate of the Advisor, is the transfer agent, dividend-paying agent and shareholder service agent for the Fund. Pursuant to a sub-transfer agency agreement between DSC and DST Systems, Inc. (“DST”), DSC has delegated certain transfer agent, dividend-paying agent and shareholder service agent functions to DST. DSC compensates DST out of the shareholder servicing fee it receives from the Fund. For the six months ended June 30, 2018, the amount charged to the Fund by DSC aggregated $33,412, of which $19,530 is unpaid.

Shareholder Servicing Fee. DWS Distributors, Inc. (“DDI”), an affiliate of the Advisor, provides information and administrative services for a fee (“Service Fee”) to shareholders at an annual rate of up to 0.25% of average daily net assets. DDI in turn has various agreements with financial services firms that provide these services and pay these fees based upon the assets of shareholder accounts the firms service. For six

months ended June 30, 2018, the Service Fee was as follows:

	Total Aggregated		Unpaid at June 30, 2018		Annualized Rate
DWS Government Cash Management Fund	$	548,876	$	209,627		.06	%

Typesetting and Filing Service Fees. Under an agreement with DIMA, DIMA is compensated for providing certain pre-press and regulatory filing services to the Fund. For the six months ended June 30, 2018, the amount charged to the Fund by DIMA included in the Statement of Operations under “Reports to shareholders“ aggregated $7,609, all of which is unpaid.

Trustees’ Fees and Expenses. The Fund paid retainer fees to each Trustee not affiliated with the Advisor, plus specified amounts to the Board Chairperson and Vice Chairperson and to each committee Chairperson.

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C. Concentration of Ownership

From time to time, the Fund may have a concentration of several shareholder accounts holding a significant percentage of shares outstanding. Investment activities of these shareholders could have a material impact on the Fund.

At June 30, 2018, there was one shareholder account that held approximately 83% of the outstanding shares of the Fund.

D. Name Changes

In connection with adoption of the DWS brand, effective July 2, 2018, Deutsche Investment Management Americas Inc., the Advisor, was renamed to DWS Investment Management Americas, Inc. In addition, the “Deutsche Funds” became known as the “DWS Funds.” As a result, Deutsche Government Cash Management Fund was renamed DWS Government Cash Management Fund.

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Information About Your Fund’s Expenses

As an investor of the Fund, you incur two types of costs: ongoing expenses and transaction costs. Ongoing expenses include management fees and other Fund expenses. Examples of transaction costs include account maintenance fees, which are not shown in this section. The following tables are intended to help you understand your ongoing expenses (in dollars) of investing in the Fund and to help you compare these expenses with the ongoing expenses of investing in other mutual funds. In the most recent six-month period, the Fund limited these expenses; had it not done so, expenses would have been higher. The example in the table is based on an investment of $1,000 invested at the beginning of the six-month period and held for the entire period (January 1, 2018 to June 30, 2018).

The tables illustrate your Fund’s expenses in two ways:

– Actual Fund Return. This helps you estimate the actual dollar amount of ongoing expenses (but not transaction costs) paid on a $1,000 investment in the Fund using the Fund’s actual return during the period. To estimate the expenses you paid over the period, simply divide your account value by $1,000 (for example, an $8,600 account value divided by $1,000 = 8.6), then multiply the result by the number in the “Expenses Paid per $1,000” line under the share class you hold.

– Hypothetical 5% Fund Return. This helps you to compare your Fund’s ongoing expenses (but not transaction costs) with those of other mutual funds using the Fund’s actual expense ratio and a hypothetical rate of return of 5% per year before expenses. Examples using a 5% hypothetical fund return may be found in the shareholder reports of other mutual funds. The hypothetical account values and expenses may not be used to estimate the actual ending account balance or expenses you paid for the period.

Please note that the expenses shown in these tables are meant to highlight your ongoing expenses only and do not reflect any transaction costs. The “Expenses Paid per $1,000” line of the tables is useful in comparing ongoing expenses only and will not help you determine the relative total expense of owning different funds. If these transaction costs had been included, your costs would have been higher.

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Expenses and Value of a $1,000 Investment for the six months ended June 30, 2018 (Unaudited)
Actual Fund Return*	Institutional Shares
Beginning Account Value 1/1/18	$	1,000.00
Ending Account Value 6/30/18	$	1,006,75
Expenses Paid per $1,000**	$	1.34
Hypothetical 5% Fund Return
Beginning Account Value 1/1/18	$	1,000.00
Ending Account Value 6/30/18	$	1,023.46
Expenses Paid per $1,000**	$	1.35

* Expenses include amounts allocated proportionally from the master portfolio.

** Expenses are equal to the Fund’s annualized expense ratio, multiplied by the average account value over the period, multiplied by 181 (the number of days in the most recent six-month period), then divided by 365.

Annualized Expense Ratio	Institutional Shares
DWS Government Cash Management Fund		.27%

For more information, please refer to the Fund’s prospectus.

For an analysis of the fees associated with an investment in the Fund or similar funds, please refer to http://apps.finra.org/fundanalyzer/1/fa.aspx.

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(The following financial statements of the Government Cash Management Portfolio should be read in conjunction with the Fund’s financial statements.)

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Investment Portfolio as of June 30, 2018 (Unaudited)

Government Cash Management Portfolio

	Principal Amount ($)		Value ($)
Government & Agency Obligations 91.6%
U.S. Government Sponsored Agencies 57.4%
Federal Farm Credit Bank:
1-month LIBOR minus 0.165%, 1.836%*, 11/2/2018		70,500,000		70,499,400
1-month LIBOR minus 0.165%, 1.881%*, 10/9/2018		37,500,000		37,499,454
1-month LIBOR minus 0.150%, 1.896%*, 10/11/2018		25,000,000		24,999,790
1-month LIBOR minus 0.135%, 1.911%*, 4/11/2019		150,000,000		150,000,000
1-month LIBOR minus 0.110%, 1.936%*, 3/12/2019		115,000,000		114,995,656
1-month LIBOR minus 0.145%, 1.949%*, 3/29/2019		166,000,000		166,000,000
1-month LIBOR minus 0.145%, 1.953%*, 2/26/2019		115,000,000		114,996,961
1-month LIBOR minus 0.130%, 1.964%*, 4/29/2019		246,500,000		246,500,000
1-month LIBOR minus 0.120%, 1.971%*, 3/25/2019		100,000,000		100,000,000
1-month LIBOR minus 0.070%, 1.976%*, 1/9/2019		50,000,000		50,000,000
1-month LIBOR minus 0.065%, 2.019%*, 7/20/2018		68,800,000		68,800,000
1-month LIBOR minus 0.003%, 2.133%*, 8/27/2018		75,000,000		74,999,088
3-month U.S. Treasury Bill Money Market Yield plus 0.280%, 2.189%*, 11/13/2018		60,000,000		60,000,000
3-month U.S. Treasury Bill Money Market Yield plus 0.300%, 2.209%*, 12/5/2018		50,000,000		50,000,000
Federal Home Loan Bank:
1.572%**, 7/2/2018		114,799,000		114,794,057
1-month LIBOR minus 0.160%, 1.822%*, 8/1/2018		200,000,000		200,000,000
1.825%**, 7/3/2018		115,500,000		115,488,450
1-month LIBOR minus 0.160%, 1.841%*, 8/3/2018		370,000,000		370,000,000
1.845%**, 7/24/2018		64,000,000		63,925,582
1-month LIBOR minus 0.155%, 1.85%*, 7/5/2018		205,000,000		205,000,000
1.86%**, 7/20/2018		75,000,000		74,927,364
1.86%**, 7/23/2018		75,000,000		74,915,896
1.87%**, 8/24/2018		78,000,000		77,784,252
1.873%**, 8/1/2018		100,000,000		99,840,953
1.88%**, 7/13/2018		286,500,000		286,322,943
1.881%**, 7/23/2018		343,250,000		342,860,888
1.886%**, 7/20/2018		800,000		799,215
1-month LIBOR minus 0.145%, 1.902%*, 8/13/2018		35,000,000		35,000,000
1-month LIBOR minus 0.090%, 1.915%*, 4/5/2019		88,000,000		88,000,000
1-month LIBOR minus 0.080%, 1.921%*, 2/4/2019		95,000,000		95,000,000
1-month LIBOR minus 0.090%, 1.923%*, 4/5/2019		150,000,000		150,000,000
1-month LIBOR minus 0.160%, 1.925%*, 7/19/2018		240,000,000		240,000,000
1-month LIBOR minus 0.130%, 1.927%*, 3/22/2019		233,250,000		233,250,000

The accompanying notes are an integral part of the financial statements.

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	Principal Amount ($)		Value ($)
1-month LIBOR minus 0.145%, 1.928%*, 8/15/2018		135,000,000		135,000,000
1-month LIBOR minus 0.150%, 1.935%*, 7/16/2018		188,000,000		188,000,000
1-month LIBOR minus 0.090%, 1.94%*, 11/8/2018		70,000,000		70,000,000
1.947%**, 9/4/2018		35,000,000		34,878,667
1-month LIBOR minus 0.135%, 1.95%*, 11/16/2018		190,000,000		190,000,000
1.951%**, 8/22/2018		585,000,000		583,374,220
1.957%**, 9/7/2018		595,000,000		592,830,894
1.957%**, 9/17/2018		25,000,000		24,895,458
1.957%**, 9/28/2018		95,000,000		94,546,715
1-month LIBOR minus 0.125%, 1.959%*, 8/20/2018		220,000,000		220,000,000
1-month LIBOR minus 0.130%, 1.961%*, 10/24/2018		120,000,000		120,000,000
1.962%**, 10/9/2018		25,000,000		24,865,625
1-month LIBOR minus 0.125%, 1.963%*, 6/21/2019		163,500,000		163,500,000
3-month LIBOR minus 0.390%, 1.965%*, 1/22/2019		5,125,000		5,125,000
1-month LIBOR minus 0.110%, 1.974%*, 2/22/2019		224,000,000		224,000,000
1-month LIBOR minus 0.120%, 1.978%*, 10/26/2018		300,000,000		300,000,000
1-month LIBOR minus 0.090%, 1.995%*, 1/18/2019		95,000,000		95,000,000
3-month LIBOR minus 0.330%, 2.005%*, 12/21/2018		155,000,000		155,000,000
1-month LIBOR minus 0.040%, 2.006%*, 7/9/2018		50,000,000		50,000,894
2.008%**, 10/25/2018		25,000,000		24,840,500
3-month LIBOR minus 0.310%, 2.017%*, 3/11/2019		210,000,000		210,000,000
1-month LIBOR minus 0.045%, 2.046%*, 1/24/2019		75,000,000		75,037,273
3-month LIBOR minus 0.250%, 2.058%*, 8/3/2018		168,000,000		168,000,000
2.069%**, 1/4/2019		607,000		600,565
3-month LIBOR minus 0.250%, 2.109%*, 7/30/2018		168,000,000		168,000,000
Federal Home Loan Mortgage Corp.:
0.875%, 10/12/2018		590,000		588,997
1.375%, 2/28/2019		906,000		901,684
1.749%**, 8/9/2018		50,000,000		49,906,562
1.774%**, 7/18/2018		200,000,000		199,834,721
1.779%**, 7/16/2018		56,000,000		55,959,050
1.784%**, 8/9/2018		22,000,000		21,958,053
1.815%**, 7/26/2018		220,000,000		219,726,528
1-month LIBOR minus 0.150%, 1.896%*, 2/12/2019		20,000,000		20,000,000
1.916%**, 8/20/2018		150,000,000		149,606,250
1-month LIBOR minus 0.16%, 1.925%*, 7/19/2018		150,000,000		150,000,000
1-month LIBOR minus 0.100%, 1.93%*, 8/8/2019		87,000,000		87,000,000
3-month LIBOR minus 0.280%, 2.073%*, 8/10/2018		100,000,000		100,000,000
3-month LIBOR minus 0.250%, 2.087%*, 10/10/2018		85,500,000		85,500,000
3-month LIBOR minus 0.250%, 2.109%*, 7/24/2018		965,000		964,962
				9,256,642,567

The accompanying notes are an integral part of the financial statements.

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	Principal Amount ($)		Value ($)
U.S. Treasury Obligations 34.2%
U.S. Treasury Bills:
1.257%**, 9/13/2018		5,000,000		4,987,255
1.832%**, 8/23/2018		300,000,000		299,202,019
1.855%**, 7/26/2018		475,000,000		474,396,353
1.86%**, 8/2/2018		200,000,000		199,673,778
1.872%**, 9/20/2018		155,000,000		154,356,207
1.886%**, 8/23/2018		16,000,000		15,956,187
1.906%**, 9/27/2018		300,000,000		298,621,334
1.916%**, 9/20/2018		125,000,000		124,468,437
1.918%**, 9/20/2018		125,000,000		124,467,875
1.921%**, 9/27/2018		366,000,000		364,304,607
1.924%**, 8/30/2018		120,000,000		119,620,400
1.977%**, 9/20/2018		280,000,000		278,771,500
2.008%**, 10/18/2018		200,000,000		198,801,000
2.009%**, 10/18/2018		85,000,000		84,490,168
2.058% **, 11/23/2018		200,000,000		198,364,722
2.059%**, 11/23/2018		108,500,000		107,612,643
U.S. Treasury Floating Rate Notes:
3-month U.S. Treasury Bill Money Market Yield plus 0.140%, 2.049%*, 1/31/2019		154,000,000		154,185,865
3-month U.S. Treasury Bill Money Market Yield plus 0.170%, 2.079%*, 10/31/2018		1,137,000,000		1,137,955,115
3-month U.S. Treasury Bill Money Market Yield plus 0.174%, 2.083%*, 7/31/2018		1,175,000,000		1,175,242,374
U.S. Treasury Notes, 0.75%, 9/30/2018		4,000,000		3,988,318
				5,519,466,157
Total Government & Agency Obligations (Cost $14,776,108,724)				14,776,108,724
Repurchase Agreements 8.3%
BNP Paribas, 2.1%, dated 6/29/2018, to be repurchased at $212,837,240 on 7/2/2018 (a)		212,800,000		212,800,000
Citigroup Global Markets, Inc., 2.1%, dated 6/29/2018, to be repurchased at $150,026,250 on 7/2/2018 (b)		150,000,000		150,000,000
Fixed Income Clearing Corp., 1.00%, dated 6/29/2018, to be repurchased at $300,025,000 on 7/2/2018 (c)		300,000,000		300,000,000
HSBC Securities, Inc., 2.11%, dated 6/29/2018, to be repurchased at $250,043,958 on 7/2/2018 (d)		250,000,000		250,000,000
Wells Fargo Bank, 2.12%, dated 6/29/2018, to be repurchased at $426,727,375 on 7/2/2018 (e)		426,652,000		426,652,000
Total Repurchase Agreements (Cost $1,339,452,000)				1,339,452,000

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	% of Net Assets		Value ($)
Total Investment Portfolio (Cost $16,115,560,724)		99.9		16,115,560,724
Other Assets and Liabilities, Net		0.1		15,655,398
Net Assets		100.0		16,131,216,122

* Floating rate security. These securities are shown at their current rate as of June 30, 2018.

** Annualized yield at time of purchase; not a coupon rate.

(a) Collateralized by:

Principal Amount ($)		Security	Rate (%)	Maturity Date		Collateral Value ($)
	95,982,500	U.S. Treasury Bonds	2.875–3.125		8/31/2022–5/31/2025		96,482,256
	106,451,100	U.S. Treasury Notes	1.25–2.875		5/15/2043–8/15/2045		107,109,770
	20,849,600	U.S. Treasury STRIPS	Zero Coupon		2/15/2033		13,464,046
	Total Collateral Value						217,056,072

(b) Collateralized by $158,000,000 U.S. Treasury Note, 1.75%, maturing on 03/31/2022 with a value of $153,000,009.

(c) Collateralized by $296,165,000 U.S. Treasury Notes, with the various coupon rates from 2.375–3.625%, with various maturity dates of 8/15/2020–2/15/2021 with a value of $306,003,436.

(d) Collateralized by $245,354,299 Government National Mortgage Association, with the various coupon rates from 3.5–5.5%, with various maturity dates of 11/20/2036–6/20/2048 with a value of $255,001,609.

(e) Collateralized by:

Principal Amount ($)		Security	Rate (%)	Maturity Date	Collateral Value ($)
	135,701,926	FREMF Mortgage Trust	0.1–3.703	11/25/2023–1/25/2046		1,262,614
	452,820	Federal Agricultural Mortgage Corp.	2.85	11/30/2021		455,314
	1,245,824	Federal Home Loan Bank	1.2–2.75	12/20/2018–6/10/2022		1,216,915
	99,000,958	Federal Home Loan Mortgage Corp.	2.00–6.50	11/1/2025–7/1/2048		99,205,939
	294,978,884	Federal National Mortgage Association	1.35–6.625	7/11/2018–8/1/2056		300,807,543
	284	Federal National Mortgage Association STRIPS	Zero Coupon	1/15/2028		207
	70,671,059	Federal National Mortgage Association- Interest Only	3.0–8.0	3/15/2029–8/25/2047		11,677,361
	55,956,981	Freddie Mac Multifamily Structured Pass-Through Certificates	0.815–2.896	3/25/2019–12/25/2041		3,294,853

The accompanying notes are an integral part of the financial statements.

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Principal Amount ($)		Security	Rate (%)	Maturity Date		Collateral Value ($)
	13,050,267	Government National Mortgage Association	2.5–10.00		2/20/2019–5/20/2048		12,796,118
	5,271,712	Tennessee Valley Authority	Zero Coupon–2.875		10/15/2018–9/15/2025		4,468,176
	Total Collateral Value						435,185,040

Interest Only: Interest Only (IO) bonds represent the “interest only” portion of payments on a pool of underlying mortgages or mortgage-backed securities. IO securities are subject to prepayment risk of the pool of underlying mortgages.

LIBOR: London Interbank Offered Rate

STRIPS: Separate Trading of Registered Interest and Principal Securities

Fair Value Measurements

Various inputs are used in determining the value of the Portfolio’s investments. These inputs are summarized in three broad levels. Level 1 includes quoted prices in active markets for identical securities. Level 2 includes other significant observable inputs (including quoted prices for similar securities, interest rates, prepayment speeds and credit risk). Level 3 includes significant unobservable inputs (including the Portfolio’s own assumptions in determining the fair value of investments). The level assigned to the securities valuations may not be an indication of the risk or liquidity associated with investing in those securities. Securities held by the Portfolio are reflected as Level 2 because the securities are valued at amortized cost (which approximates fair value) and, accordingly, the inputs used to determine value are not quoted prices in an active market.

The following is a summary of the inputs used as of June 30, 2018 in valuing the Portfolio’s investments. For information on the Portfolio’s policy regarding the valuation of investments, please refer to the Security Valuation section of Note A in the accompanying Notes to Financial Statements.

Assets	Level 1		Level 2		Level 3		Total
Investments in Securities (f)	$	—	$	14,776,108,724	$	—	$	14,776,108,724
Repurchase Agreements		—		1,339,452,000		—		1,339,452,000
Total	$	—	$	16,115,560,724	$	—	$	16,115,560,724

There have been no transfers between fair value measurement levels during the period ended June 30, 2018.

(f) See Investment Portfolio for additional detailed categorizations.

The accompanying notes are an integral part of the financial statements.

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Statement of Assets and Liabilities

as of June 30, 2018 (Unaudited)
Assets
Investments in non-affiliated securities, valued at amortized cost	$	16,115,560,724
Cash		89,877,991
Interest receivable		15,314,533
Other assets		416,468
Total assets		16,221,169,716
Liabilities
Payable for investment purchased		88,426,577
Accrued investment advisory fee		800,541
Accrued Trustees’ fees		59,032
Other accrued expenses and payables		667,444
Total liabilities		89,953,594
Net assets, at value	$	16,131,216,122

The accompanying notes are an integral part of the financial statements.

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Statement of Operations

for the six months ended June 30, 2018 (Unaudited)
Investment Income
Income:
Interest	$	152,505,763
Expenses:
Management fee		9,125,339
Administration fee		2,800,033
Custodian fee		72,562
Professional fees		140,158
Reports to shareholders		21,438
Trustees’ fees and expenses		523,492
Other		252,428
Total expenses before expense reductions		12,935,450
Expense reductions		(3,772,145	)
Total expenses after expense reductions		9,163,305
Net investment income		143,342,458
Net realized gain (loss) from investments		(30,111	)
Net increase (decrease) in net assets resulting from operations	$	143,312,347

The accompanying notes are an integral part of the financial statements.

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Statements of Changes in Net Assets

Increase (Decrease) in Net Assets	Six Months Ended June 30, 2018 (Unaudited)			Year Ended December 31, 2017
Operations:
Net investment income (loss)	$	143,342,458		$	106,771,143
Net realized gain (loss)		(30,111	)		338,378
Net increase (decrease) in net assets resulting from operations		143,312,347			107,109,521
Capital transactions in shares of beneficial interest:
Proceeds from capital invested		36,244,142,699			64,583,463,238
Value of capital withdrawn		(37,428,704,925	)		(59,493,039,509	)
Net increase (decrease) in net assets from capital transactions in shares of beneficial interest		(1,184,562,226	)		5,090,423,729
Increase (decrease) in net assets		(1,041,249,879	)		5,197,533,250
Net assets at beginning of period		17,172,466,001			11,974,932,751
Net assets at end of period	$	16,131,216,122		$	17,172,466,001

The accompanying notes are an integral part of the financial statements.

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Financial Highlights

	Six Months Ended 6/30/18			Years Ended December 31,
	(Unaudited)			2017		2016		2015		2014		2013
Ratios to Average Net Assets and Supplemental Data
Net assets, end of period ($ millions)		16,131			17,172		11,975		18,021		19,918		20,214
Ratio of expenses before expense reductions (%)		.14	*		.14		.16		.17		.17		.16
Ratio of expenses after expense reductions (%)		.10	*		.11		.11		.14		.14		.14
Ratio of net investment income (%)		1.54	*		.83		.32		.11		.05		.08
Total Return (%)a,b		.75	**		.81		.32		.11		.05		.08

^a Total return would have been lower had certain expenses not been reduced.

^b Total return for the Portfolio was derived from the performance of DWS Government Cash Reserves Fund Institutional.

^* Annualized

^** Not annualized

The accompanying notes are an integral part of the financial statements.

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Notes to Financial Statements (Unaudited)

A. Organization and Significant Accounting Policies

Government Cash Management Portfolio (the “Portfolio”) is registered under the Investment Company Act of 1940, as amended (the “1940 Act”), as an open-end management investment company organized as a New York trust.

The Portfolio is a master fund. A master/feeder fund structure is one in which a fund (a “feeder fund”), instead of investing directly in a portfolio of securities, invests most or all of its investment assets in a separate registered investment company (the “master fund”) with substantially the same investment objective and policies as the feeder fund. Such a structure permits the pooling of assets of two or more feeder funds, preserving separate identities or distribution channels at the feeder fund level. The Portfolio may have several feeder funds, including affiliated DWS feeder funds and unaffiliated feeder funds; with a significant ownership percentage of the Portfolio’s net assets. Investment activities of these feeder funds could have a material impact on the Portfolio. As of June 30, 2018, DWS Government Cash Management Fund, DWS Government Cash Reserves Fund Institutional and DWS Government Money Market Series owned approximately 11%, 2% and 84%, respectively, of the Portfolio.

The Portfolio’s financial statements are prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) which require the use of management estimates. Actual results could differ from those estimates. The Fund qualifies as an investment company under Topic 946 of Accounting Standards Codification of U.S. GAAP. The policies described below are followed consistently by the Portfolio in the preparation of its financial statements.

Security Valuation. Various inputs are used in determining the value of the Portfolio’s investments. These inputs are summarized in three broad levels. Level 1 includes quoted prices in active markets for identical securities. Level 2 includes other significant observable inputs (including quoted prices for similar securities, interest rates, prepayment speeds and credit risk). Level 3 includes significant unobservable inputs (including the Portfolio’s own assumptions in determining the fair value of investments). The level assigned to the securities valuations may not be an indication of the risk or liquidity associated with investing in those securities.

The Portfolio values all securities utilizing the amortized cost method permitted in accordance with Rule 2a-7 under the 1940 Act and certain conditions therein. Under this method, which does not take into account unrealized capital gains or losses on securities, an instrument is initially

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valued at its cost and thereafter assumes a constant accretion/amortization rate to maturity of any discount or premium. Securities held by the Portfolio are reflected as Level 2 because the securities are valued at amortized cost (which approximates fair value) and, accordingly, the inputs used to determine value are not quoted prices in an active market.

Repurchase Agreements. The Portfolio may enter into repurchase agreements, under the terms of a Master Repurchase Agreement, with certain banks and broker/dealers whereby the Portfolio, through its custodian or a sub-custodian bank, receives delivery of the underlying securities, the amount of which at the time of purchase and each subsequent business day is required to be maintained at such a level that the value is equal to at least the principal amount of the repurchase price plus accrued interest. The custodian bank or another designated subcustodian holds the collateral in a separate account until the agreement matures. If the value of the securities falls below the principal amount of the repurchase agreement plus accrued interest, the financial institution deposits additional collateral by the following business day. If the financial institution either fails to deposit the required additional collateral or fails to repurchase the securities as agreed, the Portfolio has the right to sell the securities and recover any resulting loss from the financial institution. If the financial institution enters into bankruptcy, the Portfolio’s claims on the collateral may be subject to legal proceedings.

As of June 30, 2018, the Portfolio held repurchase agreements with a gross value of $1,339,452,000. The value of the related collateral exceeded the value of the repurchase agreements at period end. The detail of the related collateral is included in the footnotes following the Portfolio’s Investment Portfolio.

Federal Income Taxes. The Portfolio is considered a Partnership under the Internal Revenue Code, as amended. Therefore, no federal income tax provision is necessary.

It is intended that the Portfolio’s assets, income and distributions will be managed in such a way that an investor in the Portfolio will be able to satisfy the requirements of Subchapter M of the Code, assuming that the investor invested all of its assets in the Portfolio.

At December 31, 2017, Government Cash Management Portfolio had an aggregate cost of investments for federal income tax purposes of $17,453,872,167.

The Portfolio has reviewed the tax positions for the open tax years as of December 31, 2017 and has determined that no provision for income tax and/or uncertain tax provisions is required in the Portfolio’s financial statements. The Portfolio’s federal tax returns for the prior three fiscal years remain open subject to examination by the Internal Revenue Service.

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Contingencies. In the normal course of business, the Portfolio may enter into contracts with service providers that contain general indemnification clauses. The Portfolio’s maximum exposure under these arrangements is unknown, as this would involve future claims that may be made against the Portfolio that have not yet been made. However, based on experience, the Portfolio expects the risk of loss to be remote.

Other. Investment transactions are accounted for on trade date. Interest income is recorded on the accrual basis. Realized gains and losses from investment transactions are recorded on an identified cost basis. All discounts and premiums are accreted/amortized for both tax and financial reporting purposes.

The Portfolio makes an allocation of its net investment income and realized gains and losses from securities transactions to its investors in proportion to their investment in the Portfolio.

B. Fees and Transactions with Affiliates

Management Agreement. Under the Investment Management Agreement with DWS Investment Management Americas, Inc. (formerly Deutsche Investment Management Americas Inc.) (“DIMA” or the “Advisor”), an indirect, wholly owned subsidiary of DWS Group GmbH & Co. KGaA (“DWS Group”), the Advisor determines the securities, instruments and other contracts relating to investments to be purchased, sold or entered into by the Portfolio.

Under the Investment Management Agreement, the Portfolio pays the Advisor a monthly management fee based on its average daily net assets, computed and accrued daily and payable monthly, at the following annual rates:

First $3.0 billion of the Portfolio’s average daily net assets	.1200%
Next $4.5 billion of such net assets	.1025%
Over $7.5 billion of such net assets	.0900%

Accordingly, for the six months ended June 30, 2018, the fee pursuant to the Investment Management Agreement was equivalent to an annualized rate (exclusive of any applicable waivers/reimbursements) of 0.10% of the Fund’s average daily net assets.

For the period from January 1, 2018 through September 30, 2018, the Advisor has contractually agreed to waive its fees and/or reimburse certain operating expenses to the extent necessary to maintain the total annual operating expenses (excluding certain expenses such as extraordinary expenses, taxes, brokerage and interest) at 0.14% of the Portfolio’s average daily net assets.

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For the period from January 1, 2018 through April 10, 2018, the Advisor had voluntarily agreed to waive its fees and/or reimburse certain operating expenses to the extent necessary to maintain the total annual operating expenses (excluding certain expenses such as extraordinary expenses, taxes, brokerage and interest) at 0.10% of the Portfolio’s average daily net assets.

For the period from April 11, 2018 through April 26, 2018, the Advisor had voluntarily agreed to waive its fees and/or reimburse certain operating expenses to the extent necessary to maintain the total annual operating expenses (excluding certain expenses such as extraordinary expenses, taxes, brokerage and interest) at 0.08% of the Portfolio’s average daily net assets.

Effective April 27, 2018 through June 30, 2018, the Advisor has voluntarily agreed to waive its fees and/or reimburse certain operating expenses to the extent necessary to maintain the total annual operating expenses (excluding certain expenses such as extraordinary expenses, taxes, brokerage and interest) at 0.10% of the Portfolio’s average daily net assets. This voluntary waiver or reimbursement may be terminated at any time at the option of the Advisor.

For the six months ended June 30, 2018, fees waived and/or expenses reimbursed are $3,772,145.

Administration Fee. Pursuant to an Administrative Services Agreement, DIMA provides most administrative services to the Portfolio. For all services provided under the Administrative Services Agreement, the Portfolio pays the Advisor an annual fee (“Administration Fee”) of 0.03% of the Portfolio’s average daily net assets, computed and accrued daily and payable monthly. For the six months ended June 30, 2018, the Administration Fee was $2,800,033, of which $491,191 is unpaid.

Filing Service Fees. Under an agreement with DIMA, DIMA is compensated for providing certain regulatory filing services to the Portfolio. For the six months ended June 30, 2018, the amount charged to the Portfolio by DIMA included in the Statement of Operations under “Reports to shareholders” aggregated $751, all of which is unpaid.

Trustees’ Fees and Expenses. The Portfolio paid retainer fees to each Trustee not affiliated with the Advisor, plus specified amounts to the Board Chairperson and Vice Chairperson and to each committee Chairperson.

C. Line of Credit

The Portfolio and other affiliated funds (the “Participants”) share in a $400 million revolving credit facility provided by a syndication of banks. The Portfolio may borrow for temporary or emergency purposes, including the meeting of redemption requests that otherwise might require the

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untimely disposition of securities. The Participants are charged an annual commitment fee which is allocated based on net assets, among each of the Participants. Interest is calculated at a rate per annum equal to the sum of the Federal Funds Rate plus 1.25 percent plus if the one-month LIBOR exceeds the Federal Funds Rate, the amount of such excess. The Portfolio may borrow up to a maximum of 33 percent of its net assets under the agreement. The Portfolio had no outstanding loans at June 30, 2018.

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Advisory Agreement Board Considerations and Fee Evaluation

Deutsche Government Cash Management Fund (now known as DWS Government Cash Management Fund) (the “Fund”), a series of Deutsche Money Market Trust (now known as Deutsche DWS Money Market Trust), invests substantially all of its assets in Government Cash Management Portfolio (the “Portfolio”) in order to achieve its investment objective. The Portfolio’s Board of Trustees approved the renewal of the Portfolio’s investment management agreement (the “Portfolio Agreement”) with Deutsche Investment Management Americas Inc. (now known as DWS Investment Management Americas, Inc.) (“DIMA”) and the Fund’s Board of Trustees (which consists of the same members as the Board of Trustees of the Portfolio) approved the renewal of the Fund’s investment management agreement with DIMA (the “Fund Agreement,” and together with the Portfolio Agreement, the “Agreements”) in September 2017. The Portfolio’s Board of Trustees and the Fund’s Board of Trustees are collectively referred to as the “Board” or “Trustees.”

In terms of the process that the Board followed prior to approving the Agreements, shareholders should know that:

– During the entire process, all of the Portfolio’s and the Fund’s Trustees were independent of DIMA and its affiliates (the “Independent Trustees”).

– The Board met frequently during the past year to discuss fund matters and dedicated a substantial amount of time to contract review matters. Over the course of several months, the Board’s Contract Committee reviewed extensive materials received from DIMA, independent third parties and independent counsel. These materials included an analysis of performance, fees and expenses, and profitability from a fee consultant retained by the Independent Trustees (the “Fee Consultant”). Based on its evaluation of the information provided, the Contract Committee presented its findings and recommendations to the Board. The Board then reviewed the Contract Committee’s findings and recommendations.

– The Board also received extensive information throughout the year regarding performance of the Portfolio and the Fund.

– The Independent Trustees regularly met privately with counsel to discuss contract review and other matters. In addition, the Independent Trustees were advised by the Fee Consultant in the course of their review of the Portfolio’s and the Fund’s contractual arrangements and considered a comprehensive report prepared by the Fee Consultant in connection with their deliberations.

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– In connection with reviewing the Agreements, the Board also reviewed the terms of the Fund’s distribution agreement, administrative services agreement, transfer agency agreement and other material service agreements.

In connection with the contract review process, the Contract Committee and the Board considered the factors discussed below, among others. The Board also considered that DIMA and its predecessors have managed the Portfolio and the Fund since their inception, and the Board believes that a long-term relationship with a capable, conscientious advisor is in the best interests of the Portfolio and the Fund. The Board considered, generally, that shareholders chose to invest or remain invested in the Fund knowing that DIMA managed the Portfolio and the Fund. DIMA is part of Deutsche Bank AG’s (“Deutsche Bank”) Asset Management (“Deutsche AM”) division. Deutsche AM is a global asset management business that offers a wide range of investing expertise and resources, including research capabilities in many countries throughout the world.

As part of the contract review process, the Board carefully considered the fees and expenses of each Deutsche fund overseen by the Board in light of the fund’s performance. In many cases, this led to the negotiation and implementation of expense caps. As part of these negotiations, the Board indicated that it would consider relaxing these caps in future years following sustained improvements in performance, among other considerations.

While shareholders may focus primarily on fund performance and fees, the Board considers these and many other factors, including the quality and integrity of DIMA’s personnel and administrative support services provided by DIMA, such as back-office operations, fund valuations, and compliance policies and procedures.

Nature, Quality and Extent of Services. The Board considered the terms of the Agreements, including the scope of advisory services provided under the Agreements. The Board noted that, under the Agreements, DIMA provides portfolio management services to the Portfolio and the Fund and that, pursuant to separate administrative services agreements, DIMA provides administrative services to the Portfolio and the Fund. The Board considered the experience and skills of senior management and investment personnel and the resources made available to such personnel. The Board reviewed the Portfolio’s and the Fund’s performance over short-term and long-term periods and compared those returns to various agreed-upon performance measures, including a peer universe compiled using information supplied by iMoneyNet, an independent fund data service. The Board also noted that it has put into place a process of identifying “Funds in Review” (e.g., funds performing poorly relative to a peer universe), and receives additional reporting from

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DIMA regarding such funds and, where appropriate, DIMA’s plans to address underperformance. The Board believes this process is an effective manner of identifying and addressing underperforming funds. Based on the information provided, the Board noted that, for the one- and three-year periods ended December 31, 2016, the Fund’s gross performance (Institutional Shares) was in the 1st quartile of the applicable iMoneyNet universe (the 1st quartile being the best performers and the 4th quartile being the worst performers).

Fees and Expenses. The Board considered the Portfolio’s and the Fund’s investment management fee schedules, the Fund’s operating expenses and total expense ratios, and comparative information provided by Broadridge Financial Solutions, Inc. (“Broadridge”) and the Fee Consultant regarding investment management fee rates paid to other investment advisors by similar funds (1st quartile being the most favorable and 4th quartile being the least favorable). With respect to management fees paid to other investment advisors by similar funds, the Board noted that the contractual fee rates paid by the Portfolio and the Fund, which include 0.03% and 0.10% fees paid to DIMA under the respective administrative services agreements, were higher than the median (3rd quartile) of the applicable Broadridge peer group (based on Broadridge data provided as of December 31, 2016). The Board noted that, although shareholders of the Fund indirectly bear the Portfolio’s management fee, the Fund does not charge an additional investment management fee. Based on Broadridge data provided as of December 31, 2016, the Board noted that the Fund’s total (net) operating expenses, which include Portfolio expenses allocated to the Fund, were higher than the median of the applicable Broadridge expense universe for Institutional Shares (4th quartile). The Board noted the expense limitation agreed to by DIMA. The Board also noted the voluntary fee waivers implemented by DIMA to ensure the Fund maintained a positive yield. The Board considered the management fee rate as compared to fees charged by DIMA to comparable Deutsche U.S. registered funds (“Deutsche Funds”) and considered differences between the Portfolio and the Fund and the comparable Deutsche Funds. The information requested by the Board as part of its review of fees and expenses also included information about institutional accounts (including any sub-advised funds and accounts) and funds offered primarily to European investors (“Deutsche Europe funds”) managed by Deutsche AM. The Board noted that DIMA indicated that Deutsche AM does not manage any institutional accounts or Deutsche Europe funds comparable to the Portfolio and the Fund. The Board considered that the Portfolio’s management fee was reduced by 0.03% at all breakpoint levels in connection with the restructuring of the Portfolio and the Fund into government money market funds in 2016.

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On the basis of the information provided, the Board concluded that management fees were reasonable and appropriate in light of the nature, quality and extent of services provided by DIMA.

Profitability. The Board reviewed detailed information regarding revenues received by DIMA under the Agreements. The Board considered the estimated costs to DIMA, and pre-tax profits realized by DIMA, from advising the Deutsche Funds, as well as estimates of the pre-tax profits attributable to managing the Fund in particular. The Board also received information regarding the estimated enterprise-wide profitability of DIMA and its affiliates with respect to all fund services in totality and by fund. The Board and the Fee Consultant reviewed DIMA’s methodology in allocating its costs to the management of the Fund. Based on the information provided, the Board concluded that the pre-tax profits realized by DIMA in connection with the management of the Fund were not unreasonable. The Board also reviewed certain publicly available information regarding the profitability of certain similar investment management firms. The Board noted that, while information regarding the profitability of such firms is limited (and in some cases is not necessarily prepared on a comparable basis), DIMA and its affiliates’ overall profitability with respect to the Deutsche Funds (after taking into account distribution and other services provided to the funds by DIMA and its affiliates) was lower than the overall profitability levels of most comparable firms for which such data was available.

Economies of Scale. The Board considered whether there are economies of scale with respect to the management of the Portfolio and the Fund and whether the Portfolio and the Fund benefit from any economies of scale. The Board noted that the Portfolio’s and the Fund’s investment management fee schedule includes fee breakpoints. The Board concluded that the Portfolio’s and the Fund’s fee schedule represents an appropriate sharing between the Portfolio and the Fund and DIMA of such economies of scale as may exist in the management of the Portfolio and the Fund at current asset levels.

Other Benefits to DIMA and Its Affiliates. The Board also considered the character and amount of other incidental benefits received by DIMA and its affiliates, including any fees received by DIMA for administrative services provided to the Portfolio and the Fund and any fees received by an affiliate of DIMA for transfer agency services provided to the Fund. The Board also considered benefits to DIMA related to brokerage and soft-dollar allocations, including allocating brokerage to pay for research generated by parties other than the executing broker dealers, which pertain primarily to funds investing in equity securities. In addition, the Board considered the incidental public relations benefits to DIMA related to Deutsche Funds advertising and cross-selling opportunities among

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DIMA products and services. The Board considered these benefits in reaching its conclusion that the Portfolio’s and the Fund’s management fees were reasonable.

Compliance. The Board considered the significant attention and resources dedicated by DIMA to documenting and enhancing its compliance processes in recent years. The Board noted in particular (i) the experience, seniority and time commitment of the individuals serving as DIMA’s and the Fund’s chief compliance officers; (ii) the large number of DIMA compliance personnel; and (iii) the substantial commitment of resources by DIMA and its affiliates to compliance matters.

Based on all of the information considered and the conclusions reached, the Board unanimously determined that the continuation of the Agreements is in the best interests of the Portfolio and the Fund. In making this determination, the Board did not give particular weight to any single factor identified above. The Board considered these factors over the course of numerous meetings, certain of which were in executive session with only the Independent Trustees and counsel present. It is possible that individual Independent Trustees may have weighed these factors differently in reaching their individual decisions to approve the continuation of the Agreements.

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Account Management Resources

Automated Information Line	Institutional Investor Services (800) 730-1313 Personalized account information, information on other DWS funds and services via touchtone telephone and the ability to exchange or redeem shares.
Web Site	liquidity.dws.com View your account transactions and balances, trade shares, monitor your asset allocation, subscribe to fund and account updates by e-mail, and change your address, 24 hours a day. Obtain prospectuses and applications, news about DWS funds, insight from DWS economists and investment specialists and access to DWS fund account information.
For More Information	(800) 730-1313, option 1 To speak with a fund service representative.
Written Correspondence	DWS PO Box 219210 Kansas City, MO 64121-9210
Proxy Voting	The Fund’s policies and procedures for voting proxies for portfolio securities and information about how the Fund voted proxies related to its portfolio securities during the most recent 12-month period ended June 30 are available on our Web site — dws.com/en-us/resources/proxy-voting — or on the SEC’s Web site — sec.gov. To obtain a written copy of the Fund’s policies and procedures without charge, upon request, call us toll free at (800) 728-3337.
Portfolio Holdings	Following the Fund’s fiscal first and third quarter-end, a complete portfolio holdings listing is filed with the SEC on Form N-Q. In addition, each month, information about the Fund and its portfolio holdings is filed with the SEC on Form N-MFP. The SEC delays the public availability of the information filed on Form N-MFP for 60 days after the end of the reporting period included in the filing. These forms will be available on the SEC’s Web site at sec.gov, and they may also be reviewed and copied at the SEC’s Public Reference Room in Washington, D.C. Information on the operation of the SEC’s Public Reference Room may be obtained by calling (800) SEC-0330. The Fund’s portfolio holdings are also posted on dws.com from time to time. Please see the Fund’s current prospectus for more information.
Principal Underwriter	If you have questions, comments or complaints, contact: DWS Distributors, Inc. 222 South Riverside Plaza Chicago, IL 60606-5808 (800) 621-1148

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Investment Management	DWS Investment Management Americas, Inc. (“DIMA” or the “Advisor”), which is part of the DWS Group GmbH & Co. KGaA (“DWS Group”), is the investment advisor for the Fund. DIMA and its predecessors have more than 90 years of experience managing mutual funds and DIMA provides a full range of investment advisory services to both institutional and retail clients. DIMA is an indirect, wholly owned subsidiary of DWS Group. DWS Group is a global organization that offers a wide range of investing expertise and resources, including hundreds of portfolio managers and analysts and an office network that reaches the world’s major investment centers. This wellresourced global investment platform brings together a wide variety of experience and investment insight across industries, regions, asset classes and investing styles.
Nasdaq Symbol	BICXX
CUSIP Number	25160K 306
Fund Number	541

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Privacy Statement

FACTS	What Does DWS Do With Your Personal Information?
Why?	Financial companies choose how they share your personal information. Federal law gives consumers the right to limit some but not all sharing. Federal law also requires us to tell you how we collect, share and protect your personal information. Please read this notice carefully to understand what we do.
What?	The types of personal information we collect and share can include: –SocialSecurity number – Account balances – Purchase and transaction history – Bank account information – Contact information such as mailing address, e-mail address and telephone number
How?	All financial companies need to share customers’ personal information to run their everyday business. In the section below, we list the reasons financial companies can share their customers’ personal information, the reasons DWS chooses to share and whether you can limit this sharing.

Reasons we can share your personal information	Does DWS share?	Can you limit this sharing?
For our everyday business purposes — such as to process your transactions, maintain your account(s), respond to court orders or legal investigations	Yes		No
For our marketing purposes — to offer our products and services to you	Yes		No
For joint marketing with other financial companies	No		We do not share
For our affiliates’ everyday business purposes — information about your transactions and experiences	No		We do not share
For our affiliates’ everyday business purposes — information about your creditworthiness	No		We do not share
For non-affiliates to market to you	No		We do not share

Questions? Call (800) 728-3337 or e-mail us at service@dws.com

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Who we are
Who is providing this notice?	DWS Distributors, Inc; DWS Investment Management Americas, Inc.; DWS Trust Company; the DWS Funds
What we do
How does DWS protect my personal information?	To protect your personal information from unauthorized access and use, we use security measures that comply with federal law. These measures include computer safeguards and secured files and buildings.
How does DWS collect my personal information?	We collect your personal information, for example, when you: – open an account – give us your contact information – provide bank account information for ACH or wire transactions – tell us where to send money – seek advice about your investments
Why can’t I limit all sharing?	Federal law gives you the right to limit only – sharing for affiliates’ everyday business purposes – information about your creditworthiness – affiliates from using your information to market to you – sharing for non-affiliates to market to you State laws and individual companies may give you additional rights to limit sharing.
Definitions
Affiliates	Companies related by common ownership or control. They can be financial or non-financial companies. Our affiliates include financial companies with the DWS or Deutsche Bank (“DB”) name, such as DB AG Frankfurt.
Non-affiliates	Companies not related by common ownership or control. They can be financial and non-financial companies. Non-affiliates we share with include account service providers, service quality monitoring services, mailing service providers and verification services to help in the fight against money laundering and fraud.
Joint marketing	A formal agreement between non-affiliated financial companies that together market financial products or services to you. DWS does not jointly market.

Rev. 3/2018, as amended 7/2018

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Notes

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Notes

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DGCMF-3

(R-028295-7 8/18)

ITEM 2.	CODE OF ETHICS
	Not applicable.
ITEM 3.	AUDIT COMMITTEE FINANCIAL EXPERT
	Not applicable
ITEM 4.	PRINCIPAL ACCOUNTANT FEES AND SERVICES
	Not applicable
ITEM 5.	AUDIT COMMITTEE OF LISTED REGISTRANTS
	Not applicable
ITEM 6.	SCHEDULE OF INVESTMENTS
	Not applicable
ITEM 7.	DISCLOSURE OF PROXY VOTING POLICIES AND PROCEDURES FOR CLOSED-END MANAGEMENT INVESTMENT COMPANIES
	Not applicable
ITEM 8.	PORTFOLIO MANAGERS OF CLOSED-END MANAGEMENT INVESTMENT COMPANIES
	Not applicable
ITEM 9.	PURCHASES OF EQUITY SECURITIES BY CLOSED-END MANAGEMENT INVESTMENT COMPANY AND AFFILIATED PURCHASERS
	Not applicable
ITEM 10.	SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS
	There were no material changes to the procedures by which shareholders may recommend nominees to the Fund’s Board.  The primary function of the Nominating and Governance Committee is to identify and recommend individuals for membership on the Board and oversee the administration of the Board Governance Guidelines. Shareholders may recommend candidates for Board positions by forwarding their correspondence by U.S. mail or courier service to Keith R. Fox, DWS Funds Board Chair, c/o Thomas R. Hiller, Ropes & Gray LLP, Prudential Tower, 800 Boylston Street, Boston, MA 02199-3600.
ITEM 11.	CONTROLS AND PROCEDURES
	(a)	The Chief Executive and Financial Officers concluded that the Registrant’s Disclosure Controls and Procedures are effective based on the evaluation of the Disclosure Controls and Procedures as of a date within 90 days of the filing date of this report.
	(b)	There have been no changes in the registrant’s internal control over financial reporting that occurred during the second fiscal quarter of the period covered by this report that has materially affected, or is reasonably likely to materially affect, the registrant’s internal controls over financial reporting.
ITEM 12.	Disclosure of Securities Lending Activities for Closed-End Management Investment Companies.
	Not applicable
ITEM 13.	EXHIBITS
	(a)(1)	Not applicable
	(a)(2)	Certification pursuant to Rule 30a-2(a) under the Investment Company Act of 1940 (17 CFR 270.30a-2(a)) is filed and attached hereto as Exhibit 99.CERT.
	(b)	Certification pursuant to Rule 30a-2(b) under the Investment Company Act of 1940 (17 CFR 270.30a-2(b)) is furnished and attached hereto as Exhibit 99.906CERT.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Registrant:	Government Cash Management Portfolio
By:	/s/Hepsen Uzcan Hepsen Uzcan President
Date:	8/29/2018

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

By:	/s/Hepsen Uzcan Hepsen Uzcan President
Date:	8/29/2018
By:	/s/Diane Kenneally Diane Kenneally Chief Financial Officer and Treasurer
Date:	8/29/2018

EX-99.CERT

President

Form N-CSRS Certification under Sarbanes Oxley Act

I, Hepsen Uzcan, certify that:

1)	I have reviewed this report, filed on behalf of Government Cash Management Portfolio, on Form N-CSRS;
2)	Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;
3)	Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations, changes in net assets, and cash flows (if the financial statements are required to include a statement of cash flows) of the registrant as of, and for, the periods presented in this report;
4)	The registrant's other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Rule 30a-3(c) under the Investment Company Act of 1940) and internal control over financial reporting (as defined in Rule 30a-3(d) under the Investment Company Act of 1940) for the registrant and have:
	a)	Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;
	b)	Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;
	c)	Evaluated the effectiveness of the registrant's disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of a date within 90 days prior to the filing date of this report based on such evaluation; and
	d)	Disclosed in this report any change in the registrant's internal control over financial reporting that occurred during the second fiscal quarter of the period covered by this report that has materially affected, or is reasonably likely to materially affect, the registrant's internal control over financial reporting; and
5)	The registrant's other certifying officer(s) and I have disclosed to the registrant's auditors and the audit committee of the registrant's board of directors (or persons performing the equivalent functions):
	a)	All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant's ability to record, process, summarize, and report financial information; and
	b)	Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant's internal control over financial reporting.

8/29/2018	/s/Hepsen Uzcan
	Hepsen Uzcan
	President

Chief Financial Officer and Treasurer

Form N-CSRS Certification under Sarbanes Oxley Act

I, Diane Kenneally, certify that:

1)	I have reviewed this report, filed on behalf of Government Cash Management Portfolio, on Form N-CSRS;
2)	Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;
3)	Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations, changes in net assets, and cash flows (if the financial statements are required to include a statement of cash flows) of the registrant as of, and for, the periods presented in this report;
4)	The registrant's other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Rule 30a-3(c) under the Investment Company Act of 1940) and internal control over financial reporting (as defined in Rule 30a-3(d) under the Investment Company Act of 1940) for the registrant and have:
	a)	Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;
	b)	Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;
	c)	Evaluated the effectiveness of the registrant's disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of a date within 90 days prior to the filing date of this report based on such evaluation; and
	d)	Disclosed in this report any change in the registrant's internal control over financial reporting that occurred during the second fiscal quarter of the period covered by this report that has materially affected, or is reasonably likely to materially affect, the registrant's internal control over financial reporting; and
5)	The registrant's other certifying officer(s) and I have disclosed to the registrant's auditors and the audit committee of the registrant's board of directors (or persons performing the equivalent functions):
	a)	All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant's ability to record, process, summarize, and report financial information; and
	b)	Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant's internal control over financial reporting

8/29/2018	/s/Diane Kenneally
	Diane Kenneally
	Chief Financial Officer and Treasurer

EX-99.906 CERT

President

Section 906 Certification under Sarbanes Oxley Act

I, Hepsen Uzcan, certify that:

1.	I have reviewed this report, filed on behalf of Government Cash Management Portfolio, on Form N-CSRS;
2.	Based on my knowledge and pursuant to 18 U.S.C. § 1350, the periodic report on Form N-CSRS (the “Report”) fully complies with the requirements of § 13 (a) or § 15 (d), as applicable, of the Securities Exchange Act of 1934 and that the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

8/29/2018	/s/Hepsen Uzcan
	Hepsen Uzcan
	President

Chief Financial Officer and Treasurer

Section 906 Certification under Sarbanes Oxley Act

I, Diane Kenneally, certify that:

1.	I have reviewed this report, filed on behalf of Government Cash Management Portfolio, on Form N-CSRS;
2.	Based on my knowledge and pursuant to 18 U.S.C. § 1350, the periodic report on Form N-CSRS (the “Report”) fully complies with the requirements of § 13 (a) or § 15 (d), as applicable, of the Securities Exchange Act of 1934 and that the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

8/29/2018	/s/Diane Kenneally
	Diane Kenneally
	Chief Financial Officer and Treasurer