CSGS Q3 2025 Earnings Report

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CSG SYSTEMS INTERNATIONAL REPORTS THIRD QUARTER 2025 RESULTS November 5, 2025 DENVER--(BUSINESS WIRE)-- CSG (NASDAQ: CSGS) today reported results for the quarter ended September 30, 2025. Financial Results: Third quarter 2025 ﬁnancial results: Total revenue was $303.6 million. GAAP operating income was $30.5 million, or an operating margin of 10.0%, and non-GAAP operating income was $54.5 million, or a non-GAAP adjusted operating margin of 19.5%. GAAP earnings per diluted share (EPS) was $0.73 and non-GAAP EPS was $1.31. Cash ﬂows from operations were $47.9 million, with non-GAAP adjusted free cash ﬂow of $43.9 million. Shareholder Returns: CSG declared its quarterly cash dividend of $0.32 per share of common stock, or a total of approximately $9 million, to shareholders. During the third quarter of 2025, CSG repurchased a total of approximately 275,000 shares of its stock for approximately $18 million. Financial Overview (unaudited) (in thousands, except per share amounts and percentages): Quarter Ended September 30, Nine Months Ended September 30, 2025 2024 Percent Changed 2025 2024 Percent Changed GAAP Results: Revenue $ 303,615$ 295,143 2.9% $ 900,196$ 880,596 2.2% Operating Income 30,459 31,822 (4.3%) 89,699 89,039 0.7% Operating Margin Percentage 10.0% 10.8% 10.0% 10.1% EPS $ 0.73 $ 0.67 9.0% $ 1.74 $ 1.83 (4.9%) Cash Flows from Operating Activities 47,943 39,459 21.5% 96,738 53,213 81.8% Non-GAAP Results: Operating Income $ 54,496$ 50,076 8.8% $ 160,443$ 141,085 13.7% Adjusted Operating Margin Percentage 19.5% 18.4% 19.5% 17.4% EPS $ 1.31 $ 1.06 23.6% $ 3.61 $ 3.08 17.2% Adjusted EBITDA 68,975 63,901 7.9% 201,292 182,050 10.6% Adjusted Free Cash Flow43,941 32,004 37.3% 90,584 36,685 146.9% 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 ®

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GAAP Results: Total revenue for the third quarter of 2025 was $303.6 million, a 2.9% increase when compared to revenue of $295.1 million for the third quarter of 2024. The increase in revenue can be mainly attributed to the continued growth of CSG’s SaaS and related solutions. GAAP operating income for the third quarter of 2025 was $30.5 million, or 10.0% of total revenue, compared to $31.8 million, or 10.8% of total revenue, for the third quarter of 2024. GAAP EPS for the third quarter of 2025 was $0.73, compared to $0.67 for the third quarter of 2024, with the increase mainly attributed to foreign currency movements. Non-GAAP Results: Non-GAAP operating income for the third quarter of 2025 was $54.5 million, or a non-GAAP adjusted operating margin of 19.5%, compared to $50.1 million, or a non-GAAP adjusted operating margin of 18.4% for the third quarter of 2024. The increase in non- GAAP operating margin can be mainly attributed to the cost efﬁciency actions discussed above. Non-GAAP EPS for the third quarter of 2025 was $1.31, compared to $1.06 for the third quarter of 2024. The increase in non-GAAP EPS is mainly due the higher non-GAAP operating income, discussed above, and foreign currency movements. Balance Sheet and Cash Flows Cash and cash equivalents as of September 30, 2025 were $158.4 million compared to $145.9 million as of June 30, 2025 and $161.8 million as of December 31, 2024. CSG had net cash ﬂows provided by operations for the third quarters ended September 30, 2025 and 2024 of $47.9 million and $39.5 million, respectively, and had non-GAAP adjusted free cash ﬂow of $43.9 million and $32.0 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 as deﬁned under the Securities Act of 1933, as amended, that are based on assumptions about a number of important factors and involve risks and uncertainties that could cause actual results to differ materially from what appears in this news release. Some of these key factors include, but are not limited to the following items: CSG derives a signiﬁcant portion of its revenue from a limited number of customers, with approximately forty percent of its revenue from its two largest customers; Fluctuations in credit market conditions, general global economic and political conditions, and foreign currency exchange rates; CSG’s ability to maintain a reliable, secure computing environment; Continued market acceptance of CSG’s products and services; CSG’s ability to continuously develop and enhance products in a timely, cost-effective, technically advanced and competitive manner; CSG’s ability to deliver its solutions in a timely fashion within budget, particularly large and complex software implementations; CSG’s dependency on the global telecommunications industry, and in particular, the North American telecommunications industry; CSG’s ability to meet its ﬁnancial expectations; Increasing competition in CSG’s market from companies of greater size and with broader presence;

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CSG’s ability to successfully integrate and manage acquired businesses or assets to achieve expected strategic, operating and ﬁnancial goals; CSG’s ability to protect its intellectual property rights; CSG’s ability to conduct business in the international marketplace; CSG’s ability to comply with applicable U.S. and International laws and regulations; CSG’s business may be disrupted, and its results of operations and cash ﬂows adversely affected by a global pandemic; and the risks and uncertainties associated with CSG’s previously disclosed entry into the Agreement and Plan of Merger, dated October 29, 2025, with NEC Corporation, Inc. and Canvas Transaction Company, Inc., including the ability of the parties to complete the proposed transaction contemplated thereby on the anticipated terms and timing, or at all. This list is not exhaustive, and readers are encouraged to review the additional risks and important factors described in CSG’s reports on Forms 10-K and 10-Q and other ﬁlings made with the SEC. CSG SYSTEMS INTERNATIONAL, INC. CONDENSED CONSOLIDATED BALANCE SHEETS-UNAUDITED (in thousands) September 30, 2025 December 31, 2024 ASSETS Current assets: Cash and cash equivalents $ 158,385$ 161,789 Settlement and merchant reserve assets 301,545 343,235 Trade accounts receivable: Billed, net of allowance of $4,331 and $3,041 268,024 266,903 Unbilled 86,064 80,173 Income taxes receivable 6,930 2,600 Other current assets 41,939 46,182 Total current assets 862,887 900,882 Non-current assets: Property and equipment, net of depreciation of $143,445 and $133,51445,292 56,595 Operating lease right-of-use assets 17,353 24,166 Software, net of amortization of $166,726 and $154,648 22,897 19,927 Goodwill 323,909 316,041 Acquired customer contracts, net of amortization of $145,489 and $133,27931,291 39,377 Customer contract costs, net of amortization of $53,643 and $44,58769,877 60,809 Deferred income taxes 83,700 73,295 Other assets 16,313 9,595 Total non-current assets 610,632 599,805 Total assets $ 1,473,519$ 1,500,687 LIABILITIES AND STOCKHOLDERS' EQUITY Current liabilities: Current portion of long-term debt $ - $ 7,500 Operating lease liabilities 5,982 11,067 Customer deposits 44,158 41,448 Trade accounts payable 42,466 36,370 Accrued employee compensation 66,414 67,944 Settlement and merchant reserve liabilities 298,419 341,924 Deferred revenue 60,184 54,424 Income taxes payable 566 7,802 Other current liabilities 56,746 46,730 Total current liabilities 574,935 615,209

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Non-current liabilities: Long-term debt, net of unamortized discounts of $11,394 and $12,128 538,606 530,997 Operating lease liabilities 21,713 25,020 Deferred revenue 26,925 26,469 Income taxes payable 2,331 2,732 Deferred income taxes 69 94 Other non-current liabilities 19,444 17,597 Total non-current liabilities 609,088 602,909 Total liabilities 1,184,023 1,218,118 Stockholders' equity: Preferred stock, par value $.01 per share; 10,000 shares authorized; zero shares issued and outstanding - - Common stock, par value $.01 per share; 100,000 shares authorized; 28,608 and 28,854 shares outstanding 722 718 Additional paid-in capital 532,082 518,215 Treasury stock, at cost; 42,286 and 41,583 shares (1,238,633) (1,194,224) Accumulated other comprehensive income (loss): Cumulative foreign currency translation adjustments (45,975) (62,290) Accumulated earnings 1,041,300 1,020,150 Total stockholders' equity 289,496 282,569 Total liabilities and stockholders' equity $ 1,473,519$ 1,500,687 CSG SYSTEMS INTERNATIONAL, INC. CONDENSED CONSOLIDATED STATEMENTS OF INCOME-UNAUDITED (in thousands, except per share amounts) Quarter Ended Nine Months Ended September 30, 2025 September 30, 2024 September 30, 2025 September 30, 2024 Revenue $ 303,615$ 295,143$ 900,196$ 880,596 Cost of revenue (exclusive of depreciation, shown separately below) 157,534 149,487 462,172 460,266 Other operating expenses: Research and development 40,300 41,665 121,619 116,171 Selling, general and administrative 65,430 63,913 195,260 186,794 Depreciation 4,301 5,313 13,899 16,286 Restructuring and reorganization charges 5,591 2,943 17,547 12,040 Total operating expenses 273,156 263,321 810,497 791,557 Operating income 30,459 31,822 89,699 89,039 Other income (expense): Interest expense (7,367) (7,778) (21,964) (22,982) Interest income 1,284 1,922 4,266 6,641 Loss on debt extinguishment - - (453) - Other, net 1,964 (2,187) (3,787) (1,455) Total other (4,119) (8,043) (21,938) (17,796) Income before income taxes 26,340 23,779 67,761 71,243 Income tax provision (5,857) (4,691) (18,881) (18,859) Net income $ 20,483 $ 19,088 $ 48,880 $ 52,384 Weighted-average shares outstanding: Basic 27,627 28,362 27,762 28,475 Diluted 27,970 28,468 28,123 28,621

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Earnings per common share: Basic $ 0.74 $ 0.67 $ 1.76 $ 1.84 Diluted 0.73 0.67 1.74 1.83 Nine Months Ended September 30, 2025 September 30, 2024 Cash ﬂows from operating activities: Net income $ 48,880$ 52,384 Adjustments to reconcile net income to net cash provided by operating activities- Depreciation 14,533 16,724 Amortization 39,874 37,467 Loss on debt extinguishment 453 - Asset impairments 94 - Loss on unrealized foreign currency transactions, net 547 225 Deferred income taxes (9,093) (189) Stock-based compensation 25,654 25,023 Subtotal 120,942 131,634 Changes in operating assets and liabilities, net of acquired amounts: Trade accounts receivable, net (9,132) (7,873) Other current and non-current assets and liabilities (14,001) (12,771) Income taxes payable/receivable (11,946) (16,194) Trade accounts payable and accrued liabilities 7,639 (48,658) Deferred revenue 3,236 7,075 Net cash provided by operating activities 96,738 53,213 Cash ﬂows from investing activities: Purchases of software, property, and equipment (11,154) (16,528) Receipts from sale of software, property, and equipment 327 - Business combinations, net of cash and settlement assets acquired of zero and $46,432- 17,293 Net cash provided by (used in) investing activities (10,827) 765 Cash ﬂows from ﬁnancing activities: Proceeds from issuance of common stock 2,245 2,416 Payments of cash dividends (27,415) (26,598) Repurchases of common stock (58,525) (42,439) Deferred acquisition payments (314) (2,488) Proceeds from long-term debt 150,625 15,000 Payments on long-term debt (151,250) (20,625) Payments of debt ﬁnancing costs (2,258) - Payments on ﬁnancing obligations (5,513) (2,191) Settlement and merchant reserve activity (43,671) (79,606) Net cash used in ﬁnancing activities (136,076) (156,531) Effect of exchange rate ﬂuctuations on cash, cash equivalents, and restricted cash5,113 (337) Net decrease in cash, cash equivalents, and restricted cash (45,052) (102,890) Cash, cash equivalents, and restricted cash, beginning of period506,763 463,876 Cash, cash equivalents, and restricted cash, end of period $ 461,711 $ 360,986 Supplemental disclosures of cash ﬂow information: Cash paid during the period for- Interest $ 23,243$ 24,592 Income taxes 39,998 35,292 Non-cash investing and ﬁnancing activities- Software, property, and equipment included in current and non-current liabilities11,868 9,830 Reconciliation of cash, cash equivalents, and restricted cash:

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Cash and cash equivalents $ 158,385$ 118,444 Settlement and merchant reserve assets 301,545 240,755 Restricted cash included in current and non-current assets 1,781 1,787 Total cash, cash equivalents, and restricted cash $ 461,711 $ 360,986 EXHIBIT 1 CSG SYSTEMS INTERNATIONAL, INC. SUPPLEMENTAL REVENUE ANALYSIS Revenue by Signiﬁcant Customers: 10% or more of Revenue Quarter Ended Quarter Ended Quarter Ended September 30, 2025 June 30, 2025 September 30, 2024 Amount % of Revenue Amount % of Revenue Amount % of Revenue Charter $ 58,859 19% $ 57,667 19% $ 59,070 20% Comcast 53,204 18% 51,415 17% 58,688 20% Revenue by Vertical Quarter Ended Quarter Ended Quarter Ended September 30, 2025 June 30, 2025 September 30, 2024 Broadband/Cable/Satellite 51% 51% 53% Telecommunications 18% 18% 18% All other 31% 31% 29% Total revenue 100% 100% 100% Revenue by Geography Quarter Ended Quarter Ended Quarter Ended September 30, 2025 June 30, 2025 September 30, 2024 Americas 85% 85% 88% Europe, Middle East and Africa 10% 11% 9% Asia Paciﬁc 5% 4% 3% Total revenue 100% 100% 100% EXHIBIT 2 CSG SYSTEMS INTERNATIONAL, INC. DISCLOSURES FOR NON-GAAP FINANCIAL MEASURES Use of Non-GAAP Financial Measures and Limitations To supplement its condensed consolidated ﬁnancial statements presented in accordance with generally accepted accounting principles (GAAP), CSG uses non-GAAP operating income, non-GAAP adjusted operating margin percentage, non-GAAP EPS, non-GAAP adjusted EBITDA, and non-GAAP adjusted free cash ﬂow. CSG believes that these non-GAAP ﬁnancial measures, when reviewed in conjunction with

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its GAAP ﬁnancial measures, provide investors with greater transparency to the information used by CSG’s management in its ﬁnancial and operational decision making. CSG uses these non-GAAP ﬁnancial measures for the following purposes: Certain internal ﬁnancial planning, reporting, and analysis; Forecasting and budgeting; Certain management compensation incentives; and Communications with CSG’s Board of Directors, stockholders, ﬁnancial analysts, and investors. These non-GAAP ﬁnancial measures are provided with the intent of providing investors with the following information: A more complete understanding of CSG’s underlying operational results, trends, and cash generating capabilities; Consistency and comparability with CSG’s historical ﬁnancial results; and Comparability to similar companies, many of which present similar non-GAAP ﬁnancial measures to investors. Non-GAAP ﬁnancial measures are not measures of performance under GAAP, and therefore should not be considered in isolation or as a substitute for GAAP ﬁnancial information. Limitations with the use of non-GAAP ﬁnancial measures include the following items: Non-GAAP ﬁnancial measures are not based on any comprehensive set of accounting rules or principles; The way in which CSG calculates non-GAAP ﬁnancial measures may differ from the way in which other companies calculate similar non-GAAP ﬁnancial measures; Non-GAAP ﬁnancial measures do not include all items of income and expense that affect CSG’s operations and that are required by GAAP to be included in ﬁnancial statements; Certain adjustments to CSG’s non-GAAP ﬁnancial measures result in the exclusion of items that are recurring and will be reﬂected in CSG’s ﬁnancial statements in future periods; and Certain charges excluded from CSG’s non-GAAP ﬁnancial measures are cash expenses, and therefore do impact CSG’s cash position. CSG compensates for these limitations by relying primarily on its GAAP results and using non-GAAP ﬁnancial measures as a supplement only. Additionally, CSG provides speciﬁc information regarding the treatment of GAAP amounts considered in preparing the non-GAAP ﬁnancial measures and reconciles each non-GAAP ﬁnancial measure to the most directly comparable GAAP measure. Non-GAAP Financial Measures: Basis of Presentation The table below outlines the exclusions from CSG’s non-GAAP ﬁnancial measures: Non-GAAP Exclusions Operating Income Adjusted Operating Margin PercentageEPS Transaction fees — X — Restructuring and reorganization charges X X X Executive transition costs X X X Acquisition-related expenses: Amortization of acquired intangible assets X X X Earn-out compensation X X X Transaction-related costs X X X Stock-based compensation X X X Gain (loss) on debt extinguishment/conversion — — X Gain (loss) on acquisitions or dispositions — — X Unusual income tax matters — — X CSG believes that excluding certain items in calculating its non-GAAP ﬁnancial measures provides meaningful supplemental information regarding CSG’s performance and these items are excluded for the following reasons: Transaction fees are primarily comprised of fees paid to third-party payment processors and ﬁnancial institutions and interchange fees under CSG’s payment services contracts. Transaction fees are included in revenue in CSG’s Income Statement (and not netted against revenue) because CSG maintains control and acts as principal over the integrated service provided under its payment services customer contracts. However, CSG excludes expense associated with

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transaction fees from the numerator and denominator in calculating its non-GAAP adjusted operating margin percentage in order to provide comparability with historical and future periods and with its peer group and competitors. Restructuring and reorganization charges are expenses that result from cost reduction initiatives and/or signiﬁcant changes to CSG’s business, to include such things as involuntary employee terminations, changes in management structure, divestitures of businesses, facility consolidations and abandonments, and fundamental reorganizations impacting operational focus and direction. These charges are not considered reﬂective of CSG’s recurring business operating results. The exclusion of these items in calculating CSG’s non-GAAP ﬁnancial measures allows management and investors an additional means to compare CSG’s current ﬁnancial results with historical and future periods. Executive transition costs include expenses incurred related to a departure of a CSG executive ofﬁcer under the terms of the related separation agreement. These types of costs are not considered reﬂective of CSG’s recurring business operating results. The exclusion of these costs in calculating CSG’s non-GAAP ﬁnancial measures allows management and investors an additional means to compare CSG’s current ﬁnancial results with historical and future periods. Acquisition-related expenses include amortization of acquired intangible assets, earn-out compensation, and transaction- related costs. Transaction-related costs, which typically include expenses related to legal, accounting, and other professional services, are direct and incremental expenses related to business acquisitions, and thus, are not considered reﬂective of CSG’s recurring business operating results. The total amount of acquisition-related expenses can vary signiﬁcantly between periods based on the number and size of acquisition activities, previously acquired intangible assets becoming fully amortized, and ultimate realization of earn-out compensation. In addition, the timing of these expenses may not directly correlate with underlying performance of the CSG’s operations. Therefore, the exclusion of acquisition-related expenses in calculating CSG’s non-GAAP ﬁnancial measures allows management and investors an additional means to compare CSG’s current ﬁnancial results with historical and future periods. Stock-based compensation results from CSG’s issuance of equity awards to its employees under incentive compensation programs. The amount of this incentive compensation in any period is not generally linked to the level of performance by employees or CSG. The exclusion of these expenses in calculating CSG’s non-GAAP ﬁnancial measures allows management and investors an additional means to evaluate the non-cash expense related to compensation included in CSG’s results of operations, and therefore, the exclusion of this item allows investors to further evaluate the cash generating capabilities of CSG’s business. Gains and losses related to the extinguishment/conversion of debt can be as a result of the reﬁnancing of CSG’s credit agreement and/or repurchase, conversion, or settlement of CSG’s convertible notes. These activities, to include any derivative activity related to debt conversions, are not considered reﬂective of CSG’s recurring business operating results. Any resulting gain or loss is generally non-cash income or expense, and therefore, the exclusion of these items allows investors to further evaluate the cash impact of these activities for cash ﬂow and liquidity purposes. In addition, the exclusion of these gains and losses in calculating CSG’s non-GAAP EPS allows management and investors an additional means to compare CSG’s current operating results with historical and future periods. Gains or losses related to the acquisition or disposition of certain of CSG’s business activities are not considered reﬂective of CSG’s recurring business operating results. Any resulting gain or loss is generally non-cash income or expense, and therefore, the exclusion of these items allows investors to further evaluate the cash impact of these activities for cash ﬂow and liquidity purposes. In addition, the exclusion of these gains and losses in calculating CSG’s non-GAAP EPS allows management and investors an additional means to compare CSG’s current operating results with historical and future periods. Unusual items within CSG’s quarterly and/or annual income tax expense can occur from such things as income tax accounting timing matters, income taxes related to unusual events, or as a result of different treatment of certain items for book accounting and income tax purposes. Consideration of such items in calculating CSG’s non-GAAP ﬁnancial measures allows management and investors an additional means to compare CSG’s current ﬁnancial results with historical and future periods. CSG also reports non-GAAP adjusted EBITDA and non-GAAP adjusted free cash ﬂow. Management believes non-GAAP adjusted EBITDA is a useful measure to investors in evaluating CSG’s operating performance, debt servicing capabilities, and enterprise valuation. CSG deﬁnes non-GAAP adjusted EBITDA as income before interest, income taxes, depreciation, amortization, stock-based compensation, foreign currency transaction adjustments, acquisition-related expenses, and unusual items, such as restructuring and reorganization charges, executive transition costs, gains and losses related to the extinguishment of debt, and gains and losses on acquisitions or dispositions, as discussed above. Additionally, management uses non-GAAP adjusted free cash ﬂow, among other measures, to assess its ﬁnancial performance and cash generating capabilities, and believes that it is useful to investors because it shows CSG’s cash available to service debt, make strategic acquisitions and investments, repurchase its common stock, pay cash dividends, and fund ongoing operations. CSG deﬁnes non-GAAP adjusted free cash ﬂow as net cash ﬂows from operating activities before earn-out compensation payments related to acquisitions less the purchases of software, property, and equipment.

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Non-GAAP Financial Measures Non-GAAP Operating Income and Non-GAAP Adjusted Operating Margin Percentage: The reconciliation of GAAP operating income to non-GAAP operating income, and calculation of CSG’s non-GAAP adjusted operating margin percentage, for the indicated periods are as follows (in thousands, except percentages): Quarter Ended September 30, Nine Months Ended September 30, 2025 2024 2025 2024 Non-GAAP Operating Income GAAP operating income $ 30,459 $ 31,822 $ 89,699 $ 89,039 Restructuring and reorganization charges (1) 5,591 2,943 17,547 12,040 Executive transition costs - - - 352 Acquisition-related expenses: Amortization of acquired intangible assets 3,474 3,929 10,385 10,174 Earn-out compensation 2,954 2,591 13,320 3,416 Transaction-related costs 3,200 32 3,200 243 Stock-based compensation (1) 8,818 8,759 26,292 25,821 Non-GAAP operating income $ 54,496 $ 50,076 $ 160,443$ 141,085 Non-GAAP Adjusted Operating Margin Percentage Revenue $ 303,615$ 295,143$ 900,196$ 880,596 Less: Transaction fees (2) (24,333) (22,524) (78,100) (71,793) Revenue less transaction fees $ 279,282$ 272,619$ 822,096$ 808,803 Non-GAAP adjusted operating margin percentage 19.5% 18.4% 19.5% 17.4% (1)Restructuring and reorganization charges include stock-based compensation, which is not included in the stock-based compensation line in the tables above and following, and depreciation, which has not been recorded to the depreciation line item on CSG’s Income Statement. (2)Transaction fees are primarily comprised of fees paid to third-party payment processors and ﬁnancial institutions and interchange fees under CSG’s payment services contracts. Transaction fees are included in revenue in CSG's Income Statement (and not netted against revenue) because CSG maintains control and acts as principal over the integrated service provided under its payment services customer contracts. However, CSG excludes expense associated with transaction fees from the numerator and denominator in calculating its non- GAAP adjusted operating margin percentage in order to provide comparability with historical and future periods and with its peer group and competitors. Non-GAAP EPS: The reconciliations of GAAP EPS to non-GAAP EPS for the indicated periods are as follows (in thousands, except per share amounts): Quarter Ended Quarter Ended September 30, 2025 September 30, 2024 Amounts EPS (4) Amounts EPS (4) GAAP net income $ 20,483 $ 0.73 $ 19,088 $ 0.67 GAAP income tax provision (3) 5,857 4,691 GAAP income before income taxes 26,340 23,779 Restructuring and reorganization charges (1) 5,591 2,943 Acquisition-related costs: Amortization of acquired intangible assets 3,474 3,929 Earn-out compensation 2,954 2,591

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Transaction-related costs 3,200 32 Stock-based compensation (1) 8,818 8,759 Non-GAAP income before income taxes 50,377 42,033 Non-GAAP income tax provision (3) (13,602) (11,979) Non-GAAP net income $ 36,775 $ 1.31 $ 30,054 $ 1.06 Nine Months Ended Nine Months Ended September 30, 2025 September 30, 2024 Amounts EPS (4) Amounts EPS (4) GAAP net income $ 48,880 $ 1.74 $ 52,384 $ 1.83 GAAP income tax provision (3) 18,881 18,859 GAAP income before income taxes 67,761 71,243 Restructuring and reorganization charges (1) 17,547 12,040 Executive transition costs - 352 Acquisition-related expenses: Amortization of acquired intangible assets 10,385 10,174 Earn-out compensation 13,320 3,416 Transaction-related costs 3,200 243 Stock-based compensation (1) 26,292 25,821 Loss on extinguishment of debt 453 - Non-GAAP income before income taxes 138,958 123,289 Non-GAAP income tax provision (3) (37,519) (35,137) Non-GAAP net income $ 101,439$ 3.61 $ 88,152 $ 3.08 (3)The GAAP effective income tax rates for the third quarters of 2025 and 2024 were approximately 22% and 20%, respectively, and for the nine months ended September 30, 2025 and 2024 were approximately 28% and 26%, respectively. The GAAP effective tax rate increases are due primarily to certain one-time beneﬁts recognized in the third quarter of 2024 and the earn-out compensation, for which a valuation allowance has been established for income tax purposes. The non-GAAP effective income tax rates for the third quarter and nine months ended September 30, 2025 were 27% in each period and for the third quarter and nine months ended September 30, 2024 were 28.5% in each period. (4)The outstanding diluted shares for the third quarter and nine months ended September 30, 2025 were 28.0 million and 28.1 million, respectively, and for the third quarter and nine months ended September 30, 2024 were 28.5 million and 28.6 million, respectively. Non-GAAP Adjusted EBITDA: CSG’s calculation of non-GAAP adjusted EBITDA and the reconciliation of CSG’s non-GAAP adjusted EBITDA measure to GAAP net income is provided below for the indicated periods (in thousands, except percentages): Quarter Ended Nine Months Ended September 30, September 30, 2025 2024 2025 2024 GAAP net income $ 20,483 $ 19,088 $ 48,880 $ 52,384 GAAP income tax provision 5,857 4,691 18,881 18,859 Interest expense (5) 7,367 7,778 21,964 22,982 Loss on debt extinguishment - - 453 - Interest income and other, net (3,248) 265 (479) (5,186) GAAP operating income 30,459 31,822 89,699 89,039 Restructuring and reorganization charges (1) 5,591 2,943 17,547 12,040 Executive transition costs - - - 352

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Acquisition-related expenses: Amortization of acquired intangible assets (6) 3,474 3,929 10,385 10,174 Earn-out compensation 2,954 2,591 13,320 3,416 Transaction-related costs 3,200 32 3,200 243 Stock-based compensation (1) 8,818 8,759 26,292 25,821 Amortization of other intangible assets (6) 4,301 3,139 11,628 8,584 Amortization of customer contract costs (6) 5,877 5,373 15,322 16,095 Depreciation (1) 4,301 5,313 13,899 16,286 Non-GAAP adjusted EBITDA $ 68,975 $ 63,901 $ 201,292$ 182,050 Non-GAAP adjusted EBITDA as a percentage of revenue less transaction fees (2) 24.7% 23.4% 24.5% 22.5% (5)Interest expense includes amortization of deferred ﬁnancing costs as provided in Note 6 below. (6)Amortization on the statement of cash ﬂows is made up of the following items for the indicated periods (in thousands): Quarter Ended Nine Months Ended September 30, September 30, 2025 2024 2025 2024 Amortization of acquired intangible assets$ 3,474 $ 3,929 $ 10,385 $ 10,174 Amortization of other intangible assets 4,301 3,139 11,628 8,584 Amortization of customer contract costs 5,877 5,373 15,322 16,095 Amortization of deferred ﬁnancing costs 839 879 2,539 2,614 Total amortization $ 14,491 $ 13,320 $ 39,874 $ 37,467 Non-GAAP Adjusted Free Cash Flow: CSG’s calculation of non-GAAP adjusted free cash ﬂow and the reconciliation of CSG’s non-GAAP adjusted free cash ﬂow measure to cash ﬂows from operating activities are provided below for the indicated periods (in thousands): Quarter Ended Nine Months Ended September 30, September 30, 2025 2024 2025 2024 Cash ﬂows from operating activities $ 47,943 $ 39,459 $ 96,738 $ 53,213 Earn-out compensation payments - - 5,000 - Purchases of software, property, and equipment (4,002) (7,455) (11,154) (16,528) Non-GAAP adjusted free cash ﬂow $ 43,941 $ 32,004 $ 90,584 $ 36,685 John Rea, SVP, Head of Finance, Treasury, Investor Relations, and ESG Reporting (210) 687-4409 E-mail: John.Rea@csgi.com Kyle Fisher, Senior Manager, Treasury and Investor Relations (303) 796-2851 E-mail: Kyle.Fisher@csgi.com Source: CSG Systems International, Inc.

Earnings release