LOS ANGELES, CA — May 11, 2005 — Mpower Communications Corp. (AMEX:MPE), The Mpower Affinity Program offers two options that target different audiences and interest levels. The Customer Affinity Program provides Mpower business customers the ability to offer their employees Mpower local and long distance residential services at a favorable price. Participating Mpower business customers can position this program as an “Employee Benefit” alongside their other benefit programs.

The second program is the Residual Affinity Program, which provides a monthly revenue stream for any group that supports the program. The amount of revenue a group receives each month is based on the revenue generated through the group. The Residual Affinity pays organizations residual on both business and residential products. These organizations can offer specially priced Mpower voice and data services to its members, patrons, supporters, etc. and receive a portion of the revenue from those sales.

One of Mpower’s new Residual Affinity Partners is Livermore Valley Education Foundation in Northern California. “I extend my appreciation to Mpower Communications and all businesses in our community that have supported the Livermore Valley Education Foundation. I am grateful that businesses, such as Mpower, have developed programs to include donations to the LVEF to support our schools. Equally impressive is the support from the residents in Livermore who participate in these programs. I am pleased that these business are community minded; providing service to their customers and support to communities in which they live,” stated Livermore School Board Member Bill Dunlop.

Added Mpower President of Sales and Marketing Jim Ferguson, “Mpower extends our value proposition beyond offering world-class services at compelling prices with our Affinity Programs. These programs are designed to support a business’s most important assets; their employees, customers, and communities in which they live. Mpower’s Residual Affinity Program, for instance, can be used to provide funding in support of schools, civic groups, or business organizations.”

About Mpower Communications
Mpower Communications (AMEX:MPE) is a leading facilities-based broadband communications provider offering a full range of data, telephony, Internet access and Web hosting services for retail business and wholesale customers. Further information about the company can be found at www.mpowercom.com.

Forward-Looking Statements
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