SEPTEMBER 14, 2004, PETALUMA, CALIFORNIA—Calix today announced the addition of Michael Flynn to the company's board of directors. Flynn, a 34-year veteran of the telecommunications industry, has significant experience in key positions at SBC Southwestern Bell (NYSE: SBC) and ALLTEL (NYSE: AT). Flynn will offer strategic guidance to Calix, assisting the company in building upon its strong track record of delivering packet-based, multi-service, ultra-broadband solutions to wireline service providers.

"Mike brings to Calix extensive knowledge of the needs of service providers and their subscribers," said Carl Russo, Calix president and CEO. "Central to helping wireline service providers prevail in the on-going battle against cable and VOIP operators is better understanding the needs of our customers' customer. Mike's lengthy and diverse experience at ALLTEL and SBC will greatly enhance our board."

"Calix is unusual in that it is one of the few large private companies that has strong customer traction in a rapidly growing market," said Flynn. "To date, Calix has deployed capacity sufficient to drive 1.5 million fiber or copper subscriber terminations, has turned up IP video in over 25 percent of its growing customer base, and has established a leadership position in the vital broadband loop carrier market."

Flynn retired in April 2004 after ten years with ALLTEL. Under his guidance, the company was the first in the industry to successfully integrate its wireline and wireless businesses. He helped lead ALLTEL's rapid growth from $3 billion in revenue in 1998 to over $8 billion in 2004, which has positioned ALLTEL as one of the leading independent service providers in the U.S. Beginning in 1994, Flynn was president of ALLTEL's Telephone Group; president of the Communications Group; and group president, CIO and special assistant to the CEO. Prior to ALLTEL, Flynn spent 24 years within the Bell System at SBC Southwestern Bell, most recently serving as president of the Arkansas Division. Flynn also serves as a director for Airspan Networks (NASDAQ: AIRN), BayPackets, and WebEx Communications (NASDAQ: WEBX).

About Calix
Calix is a leading supplier of telecommunications solutions designed to simplify all aspects of voice, data, and video service delivery to business and residential subscribers for local exchange carriers of all sizes. Providing extensive optical and metallic density, unprecedented access capacity and functional headroom, advanced management and provisioning capabilities, and broad service flexibility, the packet-based Calix C7 platform has been deployed in over 125 service provider networks throughout North America. More information about Calix can be found at www.calix.com.

This press release contains forward-looking statements that are based upon management's current expectations and are subject to risks and uncertainties. Forward-looking statements are based upon information available to us as of the date of this press release and we assume no obligation to revise or update any such forward looking statement to reflect any event or circumstance after the date of this release. Actual results and the timing of events could differ materially from current expectations.

For additional information contact:
Jeannette Bitz
Engage PR
510-748-8200 x207
jbitz@engagepr.com