Exhibit 99.1

News Release  

ACI Worldwide, Inc. Reports Financial Results for the

Quarter Ended June 30, 2017

HIGHLIGHTS*

• Q2 new bookings up 11% year over year

• Q2 revenue of $241 million, up 10% year over year

• Reiterating 2017 guidance

* Adjusted for FX fluctuations

NAPLES, FLA — July 27, 2017 — ACI Worldwide (NASDAQ: ACIW), a leading global provider of real-time electronic payment and banking solutions, today announced financial results for the quarter ended June 30, 2017. Results and comparisons discussed in the Q2 financial summary section of this press release exclude the impact of foreign currency fluctuations.

“Q2 was another strong quarter. We came in ahead of our expectations and made progress on several important initiatives,” commented Phil Heasley, President and CEO, ACI Worldwide. “Looking forward, we have large and transformational projects in the pipeline and they are progressing as expected. We remain excited about our Universal Payments software and strategy and look forward to significant growth opportunities.”

Q2 2017 FINANCIAL SUMMARY

New bookings were $137 million, which was up 11% compared to Q2 2016. Total bookings were $206 million, up 6% from last year’s quarter.

Our 12-month backlog increased $18 million to $838 million and our 60-month backlog increased $24 million to $4.1 billion during the quarter.

Revenue in Q2 was $241 million, up 10% from the same quarter last year. Recurring revenue was $189 million, or 79% of total revenue.

Net Loss in Q2 was $30 million, impacted by a previously disclosed $48 million legal judgment. Adjusted EBITDA in Q2 grew to $44 million, an increase of 105%, from $21 million in Q2 2016. After adjusting for pass through interchange revenues of $46 million and $40 million in Q2 2017 and Q2 2016, respectively, net adjusted EBITDA margin in Q2 was 22% in 2017 versus 12% in Q2 of 2016.

ACI ended Q2 2017 with $95 million in cash on hand, up from $76 million at year end, and a debt balance of $705 million, which represents a decrease of $49 million from year end. Cash flow from operating activities was $13 million in the quarter. Adjusted operating free cash flow (OFCF) for the quarter was $2 million.

REITERATE GUIDANCE

In 2017, we expect to generate revenue in a range of $1.0 billion to $1.025 billion, which represents 2-5% organic growth. Adjusted EBITDA is expected to be in a range of $250 million to $255 million, which excludes approximately $14 million in one-time integration related expenses for PAY.ON, the CFS divestiture, and data center and facilities consolidation, as well as the legal judgment. We expect to generate between $210 million and $225 million of revenue in the third quarter. We expect full year 2017 new bookings to grow in the upper single digit range.

CONFERENCE CALL TO DISCUSS FINANCIAL RESULTS AND OUTLOOK

Management will host a conference call at 8:30 am ET to discuss these results as well as 2017 guidance. Interested persons may access a real-time audio broadcast of the teleconference at http://investor.aciworldwide.com/ or use the following numbers for dial-in participation: US/Canada: (866) 914-7436, international: +1 (817) 385-9117. Please provide your name, the conference name ACI Worldwide, Inc. and conference code 52348890. There will be a replay of the call available for two weeks on (855) 859-2056 for US/Canada callers and +1 (404) 537-3406 for international participants.

About ACI Worldwide

ACI Worldwide, the Universal Payments (UP) company, powers electronic payments for more than 5,100 organizations around the world. More than 1,000 of the largest financial institutions and intermediaries, as well as thousands of global merchants, rely on ACI to execute $14 trillion each day in payments and securities. In addition, myriad organizations utilize our electronic bill presentment and payment services. Through our comprehensive suite of software solutions delivered on customers’ premises or through ACI’s private cloud, we provide real-time, immediate payments capabilities and enable the industry’s most complete omni-channel payments experience. To learn more about ACI, please visit www.aciworldwide.com. You can also find us on Twitter @ACI_Worldwide.

© Copyright ACI Worldwide, Inc. 2017.

For more information contact:

John Kraft, Vice President, Investor Relations & Strategic Analysis

ACI Worldwide

239-403-4627

john.kraft@aciworldwide.com

To supplement our financial results presented on a GAAP basis, we use the non-GAAP measures indicated in the tables, which exclude significant transaction-related expenses, as well as other significant non-cash expenses such as depreciation, amortization and stock-based compensation, that we believe are helpful in understanding our past financial performance and our future results. The presentation of these non-GAAP financial measures should be considered in addition to our GAAP results and are not intended to be considered in isolation or as a substitute for the financial information prepared and presented in accordance with GAAP. Management generally compensates for limitations in the use of non-GAAP financial measures by relying on comparable GAAP financial measures and providing investors with a reconciliation of non-GAAP financial measures only in addition to and in conjunction with results presented in accordance with GAAP. We

believe that these non-GAAP financial measures reflect an additional way to view aspects of our operations that, when viewed with our GAAP results, provide a more complete understanding of factors and trends affecting our business. Certain non-GAAP measures include:

• Adjusted EBITDA: net income plus income tax expense (benefit), net interest income (expense), net other income (expense), depreciation, amortization, and non-cash compensation, as well as significant transaction related expenses and legal judgment. Adjusted EBITDA should be considered in addition to, rather than as a substitute for, net income (loss).

ACI is also presenting adjusted operating free cash flow, which is defined as net cash provided by operating activities, plus net after-tax payments associated with employee-related actions and facility closures, plus net after-tax payments associated with significant transaction-related expenses, and less capital expenditures plus European data center and cybersecurity capital expenditures. Adjusted operating free cash flow is considered a non-GAAP financial measure as defined by SEC Regulation G. We utilize this non-GAAP financial measure, and believe it is useful to investors, as an indicator of cash flow available for debt repayment and other investing activities, such as capital investments and acquisitions. We utilize adjusted operating free cash flow as a further indicator of operating performance and for planning investing activities. Adjusted operating free cash flow should be considered in addition to, rather than as a substitute for, net cash provided by operating activities. A limitation of adjusted operating free cash flow is that it does not represent the total increase or decrease in the cash balance for the period. This measure also does not exclude mandatory debt service obligations and, therefore, does not represent the residual cash flow available for discretionary expenditures. We believe that adjusted operating free cash flow is useful to investors to provide disclosures of our operating results on the same basis as that used by our management.

ACI also includes backlog estimates, which include all license, maintenance, and services (including SaaS and Platform) specified in executed contracts, as well as revenues from assumed contract renewals to the extent that we believe recognition of the related revenue will occur within the corresponding backlog period. We have historically included assumed renewals in backlog estimates based upon automatic renewal provisions in the executed contract and our historic experience with customer renewal rates.

Backlog is considered a non-GAAP financial measure as defined by SEC Regulation G. Our 60-month backlog estimate represents expected revenues from existing customers using the following key assumptions:

• Maintenance fees are assumed to exist for the duration of the license term for those contracts in which the committed maintenance term is less than the committed license term.

• License, facilities management, and software hosting arrangements are assumed to renew at the end of their committed term at a rate consistent with our historical experiences.

• Non-recurring license arrangements are assumed to renew as recurring revenue streams.

• Foreign currency exchange rates are assumed to remain constant over the 60-month backlog period for those contracts stated in currencies other than the U.S. dollar.

• Our pricing policies and practices are assumed to remain constant over the 60-month backlog period.

Estimates of future financial results are inherently unreliable. Our backlog estimates require substantial judgment and are based on a number of assumptions as described above. These assumptions may turn out to be inaccurate or wrong, including, but not limited to, reasons outside of management’s control. For example, our customers may attempt to renegotiate or terminate their contracts for a number of reasons, including mergers, changes in their financial condition, or general changes in economic conditions in the customer’s industry or geographic location, or we may experience delays in the development or delivery of products or services specified in customer contracts which may cause the actual renewal rates and amounts to differ from historical experiences. Changes in foreign currency exchange rates may also impact the amount of revenue actually recognized in future periods. Accordingly, there can be no assurance that contracts included in backlog estimates will actually generate the specified revenues or that the actual revenues will be generated within the corresponding 60-month period.

Backlog should be considered in addition to, rather than as a substitute for, reported revenue and deferred revenue.

Forward-Looking Statements

This press release contains forward-looking statements based on current expectations that involve a number of risks and uncertainties. Generally, forward-looking statements do not relate strictly to historical or current facts and may include words or phrases such as “believes,” “will,” “expects,” “anticipates,” “intends,” and words and phrases of similar impact. The forward-looking statements are made pursuant to safe harbor provisions of the Private Securities Litigation Reform Act of 1995.

Forward-looking statements in this press release include, but are not limited to, statements regarding: (i) progress on several important initiatives; (ii) expectations regarding large and transformational projects in the pipeline and belief that they are progressing; (iii) our excitement about our Universal Payments software and strategy; (iv) expectations regarding full-year revenue and adjusted EBITDA, and new bookings growth in 2017; and (v) expectations regarding revenue in the third quarter of 2017.

All of the foregoing forward-looking statements are expressly qualified by the risk factors discussed in our filings with the Securities and Exchange Commission. Such factors include, but are not limited to, increased competition, the success of our Universal Payments strategy, demand for our products, restrictions and other financial covenants in our credit facility, consolidations and failures in the financial services industry, customer reluctance to switch to a new vendor, the accuracy of management’s backlog estimates, the maturity of certain products, our strategy to migrate customers to our next generation products, ratable or deferred recognition of certain revenue associated with customer migrations and the maturity of certain of our products, failure to obtain renewals of customer contracts or to obtain such renewals on favorable terms, delay or cancellation of customer projects or inaccurate project completion estimates, volatility and disruption of the capital and credit markets and adverse changes in the global economy, our existing levels of debt, impairment of our goodwill or intangible assets, litigation, future acquisitions, strategic partnerships and investments, the complexity of our products and services and the risk that they may contain hidden defects or be subjected to security breaches or viruses, compliance of our products with applicable legislation, governmental regulations and industry standards, our ability to protect customer information from security breaches or attacks, our compliance with privacy regulations, the protection of

our intellectual property in intellectual property litigation, exposure to credit or operating risks arising from certain payment funding methods, the cyclical nature of our revenue and earnings and the accuracy of forecasts due to the concentration of revenue-generating activity during the final weeks of each quarter, business interruptions or failure of our information technology and communication systems, our offshore software development activities, risks from operating internationally, including fluctuations in currency exchange rates, exposure to unknown tax liabilities, volatility in our stock price, and potential claims associated with our sale and transition of our CFS assets and liabilities. For a detailed discussion of these risk factors, parties that are relying on the forward-looking statements should review our filings with the Securities and Exchange Commission, including our most recently filed Annual Report on Form 10-K and our Quarterly Reports on Form 10-Q.

ACI WORLDWIDE, INC. AND SUBSIDIARIES

CONDENSED CONSOLIDATED BALANCE SHEETS

(unaudited and in thousands, except share and per share amounts)

	June 30,			December 31,
	2017			2016
ASSETS
Current assets
Cash and cash equivalents	$	95,357		$	75,753
Receivables, net of allowances of $3,468 and $3,873, respectively		195,154			268,162
Recoverable income taxes		7,192			4,614
Prepaid expenses		27,190			25,884
Other current assets		20,584			33,578
Total current assets		345,477			407,991
Noncurrent assets
Property and equipment, net		77,794			78,950
Software, net		171,476			185,496
Goodwill		915,184			909,691
Intangible assets, net		198,192			203,634
Deferred income taxes, net		111,843			77,479
Other noncurrent assets		38,337			39,054
TOTAL ASSETS	$	1,858,303		$	1,902,295
LIABILITIES AND STOCKHOLDERS’ EQUITY
Current liabilities
Accounts payable	$	36,050		$	42,873
Employee compensation		44,220			47,804
Current portion of long-term debt		17,774			90,323
Deferred revenue		106,147			105,191
Income taxes payable		5,135			11,334
Other current liabilities		103,867			78,841
Total current liabilities		313,193			376,366
Noncurrent liabilities
Deferred revenue		52,184			49,863
Long-term debt		674,803			653,595
Deferred income taxes, net		24,492			26,349
Other noncurrent liabilities		35,731			41,205
Total liabilities		1,100,403			1,147,378
Stockholders’ equity
Preferred stock		—			—
Common stock		702			702
Additional paid-in capital		611,791			600,344
Retained earnings		514,314			545,731
Treasury stock		(289,927	)		(297,760	)
Accumulated other comprehensive loss		(78,980	)		(94,100	)
Total stockholders’ equity		757,900			754,917
TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY	$	1,858,303		$	1,902,295

ACI WORLDWIDE, INC. AND SUBSIDIARIES

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS

(unaudited and in thousands, except per share amounts)

	For the Three Months Ended June 30,
	2017			2016
Revenues
Software as a service and platform as a service	$	113,469		$	102,265
License		54,180			33,510
Maintenance		56,009			60,332
Services		16,941			23,823
Total revenues		240,599			219,930
Operating expenses
Cost of revenue (1)		120,357			115,384
Research and development		34,969			46,421
Selling and marketing		28,817			28,795
General and administrative		72,527			34,520
Depreciation and amortization		22,372			21,382
Total operating expenses		279,042			246,502
Operating loss		(38,443	)		(26,572	)
Other income (expense)
Interest expense		(10,664	)		(9,715	)
Interest income		150			121
Other		(1,766	)		2,023
Total other income (expense)		(12,280	)		(7,571	)
Loss before income taxes		(50,723	)		(34,143	)
Income tax benefit		(20,914	)		(17,669	)
Net loss	$	(29,809	)	$	(16,474	)
Loss per common share
Basic	$	(0.25	)	$	(0.14	)
Diluted	$	(0.25	)	$	(0.14	)
Weighted average common shares outstanding
Basic		117,149			115,480
Diluted		117,149			115,480

(1) The cost of revenue excludes charges for depreciation but includes amortization of purchased and developed software for resale.

ACI WORLDWIDE, INC. AND SUBSIDIARIES

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS

(unaudited and in thousands)

	For the Three Months Ended June 30,
	2017			2016
Cash flows from operating activities:
Net loss	$	(29,809	)	$	(16,474	)
Adjustments to reconcile net loss to net cash flows from operating activities:
Depreciation		6,299			5,095
Amortization		19,282			19,248
Amortization of deferred debt issuance costs		1,026			1,248
Deferred income taxes		(24,202	)		(16,018	)
Stock-based compensation expense		8,343			13,307
Other		(95	)		(364	)
Changes in operating assets and liabilities, net of impact of acquisitions:
Receivables		(13,469	)		(5,289	)
Accounts payable		(240	)		9,633
Accrued employee compensation		8,161			8,910
Current income taxes		(6,253	)		(6,916	)
Deferred revenue		(8,208	)		377
Other current and noncurrent assets and liabilities		52,576			6,289
Net cash flows from operating activities		13,411			19,046
Cash flows from investing activities:
Purchases of property and equipment		(5,243	)		(13,590	)
Purchases of software and distribution rights		(8,587	)		(3,618	)
Net cash flows from investing activities		(13,830	)		(17,208	)
Cash flows from financing activities:
Proceeds from issuance of common stock		748			801
Proceeds from exercises of stock options		914			7,749
Repurchase of restricted stock for tax withholdings		(1,615	)		(1,406	)
Repurchases of common stock		—			(7,640	)
Repayment of revolving credit facility		—			(13,000	)
Repayment of term portion of credit agreement		(5,188	)		(23,823	)
Payments on other debt and capital leases		(1,392	)		(3,940	)
Net cash flows from financing activities		(6,533	)		(41,259	)
Effect of exchange rate fluctuations on cash		2,565			(2,485	)
Net decrease in cash and cash equivalents		(4,387	)		(41,906	)
Cash and cash equivalents, beginning of period		99,744			94,369
Cash and cash equivalents, end of period	$	95,357		$	52,463

ACI Worldwide, Inc.

Reconciliation of Selected GAAP Measures to Non-GAAP Measures

	Quarter Ended June 30,
Reconciliation of Adjusted Operating Free Cash Flow (millions)	2017			2016
Net cash provided by operating activities	$	13.4		$	18.4
Net after-tax payments associated with employee-related actions		1.3			2.0
Net after-tax payments associated with facility closures		0.2			—
Net after-tax payments associated with significant transaction related expenses		0.7			3.1
Less capital expenditures		(13.8	)		(17.2	)
Plus capital expenditures for European datacenter and cyber security		—			6.8
Adjusted Operating Free Cash Flow	$	1.8		$	13.1

	Quarter Ended
	June 30,
Adjusted EBITDA (millions)	2017			2016
Net loss	($	29.8	)	($	16.5	)
Plus:
Income tax benefit		(20.9	)		(17.7	)
Net interest expense		10.5			9.6
Net other expense (income)		1.8			(2.0	)
Depreciation expense		6.3			5.1
Amortization expense		19.3			19.3
Non-cash compensation expense		8.3			13.3
Adjusted EBITDA before significant transaction related expenses and legal judgment	($	4.5	)	$	11.1
Legal judgment		46.7			—
Employee related actions		0.1			2.1
Facility closures		0.4			2.2
Significant transaction related expenses		1.1			3.9
Adjusted EBITDA	$	43.8		$	19.3
	Quarter Ended June 30,
Adjusted EBITDA excluding CFS impact (millions)	2017			2016
Total Adjusted EBITDA	$	43.8		$	19.3
Retained indirect costs during TSA period		—			2.1
Total Adjusted EBITDA excluding CFS impact	$	43.8		$	21.4

	Quarter Ended
	June 30,
Recurring Revenue (millions)	2017		2016
Monthly SaaS and platform fees	$	113.5	$	102.3
Maintenance fees		56.0		60.3
Monthly license fees		19.5		18.3
Recurring Revenue	$	189.0	$	180.9