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): December 6, 2024

CSG SYSTEMS INTERNATIONAL, INC.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (303) 200-2000

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 Instructions A.2. below):

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 5.02. Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On December 6, 2024, the Board of Directors of CSG Systems International, Inc. (“CSG”) approved the grant of a performance-based award (the “Award”) to Brian A. Shepherd, President and Chief Executive Officer, comprised of 74,475 shares of restricted stock (the “Target Shares”), with a grant date value of $4.0 million based on the closing price of CSG common stock on the date of grant, representing a 100% achievement, with a right to earn additional shares representing up to 200% of such Target Shares (the “Overperformance Shares”). The Award has a five-year performance period and vests, to the extent performance goals are achieved, in tranches over three to five years. The Award is intended to ensure leadership continuity and drive long-term value creation for CSG’s shareholders. The stock price thresholds are intended to incentivize sustained stock price performance reflective of transformational results.

The Award vests contingent upon the achievement of predetermined stock price thresholds over a five-year period, subject to time-based service vesting conditions. Tranches 1 and 2 represent the Target Shares and Tranches 3 and 4 represent the Overperformance Shares. The attainment levels and service vesting periods at each threshold are indicated in the following table:

The stock price threshold will be deemed achieved as of the date on which the 90 calendar day trailing average per share closing stock price equals or exceeds that stock price threshold. Subject to continued employment with CSG per the terms of the Award, each tranche of the Award will vest on the later of: (i) the achievement of the applicable stock price threshold; or (ii) the applicable service vesting date. Any Target Shares or Overperformance Shares, in each case, that do not vest by December 10, 2029 will be forfeited.

Under the terms of the Award, the Award may vest in full or in part, to the extent that stock price thresholds have been met, upon an involuntary termination of employment (including a constructive termination) following a change in control.

The Award agreement is attached as Exhibit 10.80

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits

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.