Amendment to Current Report (Form 8-K/A)

CSG Systems INTERNATIONAL reports

FOURTH Quarter AND FULL YEAR 2025 RESULTS

DENVER--(February 4, 2026) - CSG® (NASDAQ: CSGS) today reported results for the quarter and year ended December 31, 2025.

Financial Results:

Fourth quarter 2025 financial results:

Full year 2025 financial results:

Shareholder Returns:

CSG Systems International, Inc.

February 4, 2025

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Plan of Merger

On October 29, 2025, CSG entered into an Agreement and Plan of Merger (the "Merger Agreement") with NEC Corporation, a company incorporated under the laws of Japan ("NEC") and Canvas Transaction Company, Inc., a Delaware corporation and a wholly owned subsidiary of NEC (the "Merger"). On January 30, 2026, CSG's stockholders approved the adoption of the Merger Agreement at the special meeting of CSG's stockholders convened for such purpose. The Merger is expected to close by the end of 2026, subject to the satisfaction of the remaining customary closing conditions and required regulatory approvals.

Financial Overview (unaudited)

(in thousands, except per share amounts and percentages):

For additional information and reconciliations regarding CSG's use of non-GAAP financial measures, please refer to the attached Exhibit 2 and the Investor Relations section of CSG's website at csgi.com.

Results of Operations

GAAP Results: Total revenue for the fourth quarter of 2025 was $323.1 million, a 2.0% increase when compared to revenue of $316.7 million for the fourth quarter of 2024. Total revenue for the full year 2025 was $1,223.3 million, a 2.2% increase when compared to revenue of $1,197.2 million for the full year 2024. The increases in revenue can be mainly attributed to the continued growth of CSG's SaaS and related solutions.

GAAP operating income for the fourth quarter of 2025 was $29.1 million, or 9.0% of total revenue, compared to $42.3 million, or 13.4% of total revenue, for the fourth quarter of 2024. GAAP operating income for the full year 2025 was $118.7 million, or 9.7% of total revenue, compared to $131.3 million, or 11.0% of total revenue, for the full year 2024. The decreases in GAAP operating income can mainly be attributed to the impact of the Merger transaction-related costs and higher stock-based compensation as a result of accelerating the vesting of certain stock awards.

GAAP EPS for the fourth quarter of 2025 was $0.25, compared to $1.21 for the fourth quarter of 2024. GAAP EPS for the full year 2025 was $1.98, compared to $3.03 for the full year 2024. The decreases in GAAP EPS are mainly attributed to the lower GAAP operating income, discussed above, and a higher GAAP effective income tax rate, as 2024 EPS benefited from a lower effective tax rate due to the release of valuation allowances related to certain U.S. and foreign deferred tax assets and certain one-time benefits.

CSG Systems International, Inc.

February 4, 2025

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Non-GAAP Results: Non-GAAP operating income for the fourth quarter of 2025 was $65.8 million, or a non-GAAP adjusted operating margin of 22.3%, compared to $58.3 million, or a non-GAAP adjusted operating margin of 20.1% for the fourth quarter of 2024. Non-GAAP operating income for the full year 2025 was $226.2 million, or a non-GAAP adjusted operating margin of 20.3%, compared to $199.4 million, or a non-GAAP adjusted operating margin of 18.1% for the full year 2024. The increases in non-GAAP operating margin can be mainly attributed to cost efficiency actions taken during 2024 and 2025.

Non-GAAP EPS for the fourth quarter of 2025 was $1.53, compared to $1.65 for the fourth quarter of 2024. The decrease in non-GAAP EPS is mainly due to a higher non-GAAP effective tax rate and foreign currency movements. Non-GAAP EPS for the full year 2025 was $5.14, compared to $4.72 for the full year 2024. The increase in non-GAAP EPS for the full year is mainly due the higher non-GAAP operating income, discussed above, offset by foreign currency movements and a higher non-GAAP effective income tax rate in 2025.

Balance Sheet and Cash Flows

Cash and cash equivalents as of December 31, 2025 were $180.0 million compared to $158.4 million as of September 30, 2025 and $161.8 million as of December 31, 2024. CSG had net cash flows provided by operations for the fourth quarters ended December 31, 2025 and 2024 of $59.2 million and $82.5 million, respectively, and had non-GAAP adjusted free cash flow of $55.8 million and $76.6 million, respectively. For the year ended December 31, 2025 and 2024, CSG generated net cash flows from operations of $155.9 million and $135.7 million, respectively, and had non-GAAP adjusted free cash flow of $146.4 million and $113.3 million, respectively.

Additional Information

For information about CSG, please visit CSG's website at csgi.com. Additional information can be found in the Investor Relations section of the website.

About CSG

CSG empowers companies to build unforgettable experiences, making it easier for people and businesses to connect with, use and pay for the services they value most. Our customer experience, billing and payments solutions help companies of any size make money and make a difference. With our SaaS solutions, company leaders can take control of their future and tap into guidance along the way from our fiercely committed and forward-thinking CSGers around the world.

Want to be future-ready and a change-maker like the global brands that trust CSG? Visit csgi.com to learn more.

Forward-Looking Statements

This news release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. We intend such forward-looking statements to be covered by the safe harbor provisions for forward-looking statements contained in Section 27A of the Securities Act of 1933, as amended (the "Securities Act") and Section 21E of the Securities Exchange Act of 1934, as amended (the "Exchange Act").

CSG Systems International, Inc.

February 4, 2025

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Forward-looking statements relate to future events and typically address our expected future business and financial performance. All statements in this news release that are not historical facts are forward-looking statements. Words such as "expect," "anticipate," "intend," "plan," "aspire," "believe," "seek," "see," "will," "would," "may," "target," and similar expressions and variations or negatives of these words, typically identify such forward-looking statements. These forward-looking statements include, but are not limited to, statements relative to the Company's future plans and prospects, our financial condition, and our expectations concerning our business and the industries we serve, and the Company's expectations, plans, intentions, strategies or prospects with respect to the proposed Merger.

Such forward-looking statements are neither promises nor guarantees, but involve a number of known and unknown risks, uncertainties and assumptions that may cause our actual results, performance or achievements to differ materially from those expressed or implied in the forward-looking statements due to various factors, including, but not limited to: we derive a significant portion of our revenue from a limited number of customers; fluctuations in credit market conditions, general global economic and political conditions, and foreign currency exchange rates; our ability to maintain a reliable, secure computing environment; continued market acceptance of our products and services; our ability to continuously develop and enhance products in a timely, cost-effective, technically advanced and competitive manner; our ability to deliver its solutions in a timely fashion within budget, particularly large and complex software implementations; our dependency on the global telecommunications industry, and in particular, the North American telecommunications industry; our ability to meet our financial expectations; increasing competition in our market from companies of greater size and with broader presence; our ability to successfully integrate and manage acquired businesses or assets to achieve expected strategic, operating and financial goals; our ability to protect its intellectual property rights; our ability to conduct business in the international marketplace; our ability to comply with applicable U.S. and International laws and regulations; the ability of the parties to the Merger to complete the proposed Merger on the anticipated terms and timing, or at all; the satisfaction or waiver of other conditions to the completion of the proposed Merger; the risk that our stock price may fluctuate during the pendency of the proposed Merger and may decline if the proposed Merger is not completed; potential litigation relating to the proposed Merger that could be instituted against use or our directors, managers or officers, including the delay, expense or other effects of any outcomes related thereto; the risk that disruptions from the proposed Merger will harm our business, including current plans and operations, including during the pendency of the proposed Merger; our ability to retain, motivate, and hire key personnel; the diversion of management's time and attention from ordinary course business operations to completion of the proposed Merger and integration matters; potential adverse reactions or changes to business relationships resulting from the announcement, pendency or completion of the proposed Merger; legislative, regulatory and economic developments; potential business uncertainty, including changes to existing business relationships, during the pendency of the proposed Merger that could affect our financial performance; certain restrictions during the pendency of the proposed Merger that may impact our ability to pursue certain business opportunities or strategic transactions; unpredictability and severity of catastrophic events, including but not limited to acts of terrorism, outbreaks of war or hostilities or global pandemics, as well as management's response to any of the aforementioned factors; the possibility that the proposed Merger may be more expensive to complete than anticipated, including as a result of unexpected factors or events; unexpected costs, liabilities or delays associated with the Merger; the response of competitors to the Merger; the occurrence of any event, change or other circumstance that could give rise to the termination of the proposed Merger, including in circumstances requiring us to pay a termination fee; the ability to realize the anticipated benefits of the Merger, including the expected synergies and cost saving; the possibility that competing or superior acquisition proposals for the Company will be made; the risks identified Part I, Item 1A. "Risk Factors" of our most recent Annual Report on Form 10-K and in other filings we make with the Securities and Exchange Commission.