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SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

SCHEDULE TO
TENDER OFFER STATEMENT UNDER SECTION 14(d)(1) OR 13(e)(1)
OF THE SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 3)

CSG Systems International, Inc.
(Name of Subject Company (Issuer))

CSG Systems International, Inc.
(Name of Filing Person (Offeror))

Certain Outstanding Options to Purchase Common Stock of CSG Systems International, Inc.
(Title of Class of Securities)

126349109
(CUSIP Number of Class of Securities)
(Underlying Common Stock)

Joseph T. Ruble, Esq.
General Counsel and Secretary
CSG Systems International, Inc.
7887 East Belleview Avenue, Suite 1000
Englewood, Colorado 80111
Telephone: (303) 796-3955

Copy To:
Howard J. Kaslow, Esq.
Abrahams Kaslow & Cassman LLP
8712 West Dodge Road, Suite 300
Omaha, Nebraska 68114
Telephone: (402) 392-1250
(Name, Address and Telephone Number of Person
Authorized to Receive Notices and Communications on Behalf of Filing Persons)

CALCULATION OF FILING FEE

Transaction Valuation*
   Amount of Filing Fee
$ 18,208,317   $ 1,473.05
*
Estimated solely for purposes of calculating the amount of the filing fee. This amount assumes that options to purchase 3,925,124 shares of common stock of CSG Systems International, Inc. will be exchanged for shares of restricted stock and cancelled pursuant to this offer. In accordance with Rule 0-11 under the Securities Exchange Act of 1934, as amended, the fee is based on the product of (i) the approximate aggregate value of such options as of November 11, 2003 ($18,208,317), calculated using the Black-Scholes option pricing model, as the transaction value multiplied by (ii) $80.90 per each $1.0 million of the value of the transaction.

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Check the box if any part of the fee is offset as provided by Rule 0-11(a)(2) and identify the filing with which the offsetting fee was previously paid. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.

Amount Previously Paid:   $1,473.05

Form or Registration No.:
 
Schedule TO

Filing Party:
 
CSG Systems International, Inc.

Date Filed:
 
November 18, 2003
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Check the box if the filing relates solely to preliminary communications made before the commencement of a tender offer.

        Check the appropriate boxes below to designate any transactions to which the statement relates:

Check the following box if the filing is a final amendment reporting the results of the tender offer. ý

        This final Amendment No. 3 amends and supplements the Tender Offer Statement on Schedule TO filed with the Securities and Exchange Commission on November 18, 2003, by CSG Systems International, Inc. (the "Company") relating to the Company's Offer to Exchange Shares of Restricted Stock for Certain Outstanding Stock Options Having an Exercise Price of $17.50 per Share or More, as such Schedule TO was previously amended and supplemented by Amendments No. 1 and No. 2 thereto filed on December 10, 2003, and December 18, 2003, respectively. This final Amendment No. 3 corrects the numbers appearing in the supplemental sentences to Item 4(a) contained in such Amendment No. 2.


Item 4. Terms of the Transaction.

        Item 4(a) of the Schedule TO as previously filed hereby is supplemented by the following sentences, which replace the sentences added by Amendment No. 2 to the Schedule TO:

        The offer made by the Offer to Exchange expired at 5:00 p.m. Eastern Time on December 17, 2003. Subject to and upon the terms and conditions set forth in the Offer to Exchange, on December 18, 2003, the Company accepted for exchange and cancelled stock options covering a total of 3,617,335 shares of common stock of the Company which were properly elected for exchange and not withdrawn. Effective as of December 18, 2003, in exchange for such cancelled stock options, the Company granted a total of 1,214,119 restricted shares of its common stock. Employees eligible to participate in the exchange elected to exchange options covering approximately 92.7% of the total number of shares covered by options that were eligible for exchange.

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SIGNATURE

        After due inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.


 
 
CSG SYSTEMS INTERNATIONAL, INC.

Date: January 15, 2004
 
By:
 
/s/  PETER E. KALAN      
Peter E. Kalan, Executive Vice President and Chief Financial Officer

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