8-K

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 8-K

CURRENT REPORT
Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): February 20, 2009

Tesoro Corporation

(Exact name of registrant as specified in its charter)

Delaware	1-3473	95-0862768
(State or other jurisdiction	(Commission File Number)	(IRS Employer Identification No.)
of incorporation)

300 Concord Plaza Drive
San Antonio, Texas	78216-6999
(Address of principal executive offices)	(Zip Code)

(210) 828-8484
(Registrant’s telephone number,
including area code)

Not Applicable
(Former name or former address, if
changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2.):

o Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 7.01 Regulation FD Disclosure.

Tesoro Corporation (or the “Company”) held a conference call on February 20, 2009 at 8:00 a.m. CDT, regarding the 2008 fourth quarter and full year results, including information presented in a slide presentation (the “Slide Presentation”) that is available at www.tsocorp.com. The Slide Presentation is filed as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated herein by reference.

The Slide Presentation is being furnished, not filed, pursuant to Item 7.01 of Form 8-K. Accordingly, the information in Item 7.01 of this Current Report, including the Slide Presentation, will not be incorporated by reference into any registration statement filed by the Company under the Securities Act of 1933, as amended, unless specifically identified therein as being incorporated by reference.

Item 9.01 Financial Statements and Exhibits.

     (d) Exhibits.

99.1 Slide Presentation dated as of February 20, 2009.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934 the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Date: February 20, 2009

TESORO CORPORATION
By:	/s/ GREGORY A. WRIGHT
	Gregory A. Wright
	Executive Vice President, Chief Financial Officer

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Index to Exhibits

Exhibit Number	Description
99.1	Slide Presentation dated as of February 20, 2009.

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EX-99.1

Exhibit 99.1

February 20, 2008 4Q 2008 Earnings

Forward Looking Statements This Presentation includes forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. These statements relate to, among other things, projections of refining margins, debt reduction, cash flows and capital expenditures. We have used the words "anticipate", "believe", "could", "estimate", "expect", "intend", "may", "plan", "predict", "project", "should", "will" and similar terms and phrases to identify forward-looking statements in this Presentation. Although we believe the assumptions upon which these forward-looking statements are based are reasonable, any of these assumptions could prove to be inaccurate and the forward-looking statements based on these assumptions could be incorrect. Our operations involve risks and uncertainties, many of which are outside our control, and any one of which, or a combination of which, could materially affect our results of operations and whether the forward-looking statements ultimately prove to be correct. Actual results and trends in the future may differ materially from those suggested or implied by the forward-looking statements depending on a variety of factors which are described in greater detail in our filings with the SEC. All future written and oral forward-looking statements attributable to us or persons acting on our behalf are expressly qualified in their entirety by the previous statements. We undertake no obligation to update any information contained herein or to publicly release the results of any revisions to any forward-looking statements that may be made to reflect events or circumstances that occur, or that we become aware of, after the date of this Presentation.

1Q 2009 Guidance Pacific Northwest Mid-Pacific Mid-Continent California Throughput (mbpd) 110-120 65-75 95-105 250-260 Opex ($/bbl) $ 5.00 $ 2.90 $ 3.45 $ 7.20 $ in millions, unless noted Corporate/System Refining Depreciation $ 85 Corporate Expense $ 45 Interest Expense Before Interest Income $ 25 Marginal Tax Rate (%) 39%

Net Income 2Q 2007 3Q 2007 1Q 2008 2Q 2008 3Q 2008 4Q 2008 200 47 -82 4.464 259 97 Net Income 1Q 2008 2Q 2008 3Q 2008 4Q 2008 -0.6 0.03 1.86 0.7 2003-2006 Average $ in millions, except per share amounts 1Q 2008 2Q 2008 3Q 2008 4Q 2008 Refining $ (87) $ 85 $ 476 $ 153 Retail (28) (11) 34 51 Corporate and Unallocated (43) (47) (58) (54) Interest and Financing Costs (24) (29) (30) (28) Interest Income and Other 47 5 3 2 Net Foreign Currency (Loss) / Gain (3) (5) - 20 Income Tax (Provision) / Benefit 56 6 (166) (47) Net Income $ (82) $ 4 $ 259 $ 97 EPS (Diluted) $ (0.60) $ 0.03 $ 1.86 $ 0.70 EPS (Diluted)

4Q 2008 Segment Operating Income Bridge 3Q 2008 Market Environment LIFO Impact Wholesale and Retail Marketing Other 4Q 2008 Op Income 510 336 260 224 204 204 Bridge 174 76 36 20 $ in millions

2008 Cash Flow Available Cash Capex Revolver and Debt Repayment Dividend and Other Ending Cash Cash Flow 23 129 73 20 20 716 650 56 53 Asset Sales 40 Beginning Cash 23 Operating Cash Flow 716 Asset Sales 40 $ in millions

4Q 2008 Gross Margin Reconciliation $/bbl, unless noted Reported Gross Margin LIFO Hedge* Revised Gross Margin** California California WC 3-2-1*** $11.03 $11.03 Capture Rate**** 124% 85% Gross Margin $13.66 $1.66 $2.64 $9.36 Pacific Northwest Pacific Northwest PNW 5-3-1-1*** $9.15 $9.15 Capture Rate**** 20% (6)% Gross Margin $1.83 $1.54 $0.88 $(0.59) Mid-Pacific Mid-Pacific PNW 5-3-1-1*** $9.15 $9.15 Capture Rate**** 253% 346% Gross Margin $23.14 $(9.81) $1.28 $31.67 Mid-Continent Mid-Continent G3 3-2-1*** $6.27 $6.27 Capture Rate**** 268% 270% Gross Margin $16.82 $(0.72) $0.59 $16.95 * Hedge gains and losses are recorded primarily in the region in which the barrels are received. ** Reported gross margin per barrel adjusted to exclude the impacts of our 2008 4th Quarter LIFO impacts and gains on derivative positions. *** For more information and detail on the benchmark crack spreads, please see the 'Industry Differentials' document in the Investors section of www.tsocorp.com **** Amounts may not recalculate due to rounding.

Throughput By Refining Region 4Q 2007 4Q 2008 Guidance 4Q 2008 Actual 2007 Planned 180 150 138 Pacific Northwest Mid-Pacific Mid-Continent California 4Q 2007 4Q 2008 Guidance 4Q 2008 Actual 2007 Planned 111 110 100 4Q 2007 4Q 2008 Guidance 4Q 2008 Actual 2007 Planned 74 65 66 4Q 2007 4Q 2008 Guidance 4Q 2008 Actual 2007 Planned 274 260 251

Operating Expense By Refining Region 4Q 2007 4Q 2008 Guidance 4Q 2008 Actual 2007 Planned 7.01 7.15 6.13 Pacific Northwest Mid-Pacific Mid-Continent California 4Q 2007 4Q 2008 Guidance 4Q 2008 Actual 2007 Planned 2.9 2.85 3.52 4Q 2007 4Q 2008 Guidance 4Q 2008 Actual 2007 Planned 3.55 4.05 4.19 4Q 2007 4Q 2008 Guidance 4Q 2008 Actual 2007 Planned 3.32 3.45 3.5