Providing Business Communications Alternative in 24 U.S. Cities

MIAMI, June 28, 2000 - Telecommunications services are a major recurring expense for small and medium-sized companies, but with the arrival of Allegiance Telecom, business owners in the Miami area now have an economical alternative for local calling and related telecom services. Allegiance is targeting small and medium-sized businesses in Miami, providing local, long distance, international calling, high-speed data transmission, Internet and electronic commerce service offerings.

Allegiance is a facilities-based competitive local exchange carrier (CLEC), offering businesses a complete package of telecommunications services, consolidated on a single bill. The company is targeting 36 major metropolitan areas in the United States with its "one-stop shopping" approach. Allegiance Telecom is currently operational in 24 markets including: Atlanta, Baltimore, Boston, Chicago, Cleveland, Dallas, Denver, Detroit, Fort Worth, Houston, Long Island, Los Angeles, Miami, New York, Northern New Jersey, Oakland, Orange County, Philadelphia, St. Louis, San Diego, San Francisco, San Jose, Seattle and Washington D.C.

"Business owners in Miami depend on telecommunications services, from basic local dial tone to high-speed Internet access and e-commerce applications," said Tony Parella, Allegiance Telecom senior vice president of sales and customer care. "Allegiance is an excellent alternative to incumbent telecom providers; we offer an economical single source for business telecom services with 10 to 20 percent savings over current bills."

Parella noted the new Allegiance Telecom office will be headed by Scott Belazi, a veteran Allegiance salesperson who has been promoted to Miami city vice president from a sales management position in the company's Atlanta office. Allegiance Telecom's new local sales office is located at 7205 Corporate Center Drive in Miami, and can be reached via telephone, 305/436-1830.

The opening of the Miami office marks the completion of Allegiance Telecom's initial 24 market rollout, a plan announced when Royce J. Holland and Thomas M. Lord founded the company in 1997. Previously, Holland was president and one of several co-founders of MFS Communications Company, Inc.; Lord was a managing director at Bear, Stearns & Co. overseeing transactions in the telecommunications, information services and technology industries. Under Holland's leadership, MFS grew from a privately held start-up operation to one of the Nasdaq 100 Index companies with annual revenue of about $1 billion and a market value of approximately $13 billion when the merger between MFS and WorldCom was completed on December 31, 1996.

Allegiance Telecom is a facilities-based CLEC headquartered in Dallas, Texas. The company's web address is www.allegiancetele.com. Allegiance's common stock is traded on the Nasdaq National Market under the symbol ALGX.