MCI Communications Corporation (originally Microwave Communications, Inc.) was an American telecommunications company headquartered in Washington, D.C. that was at one point the second-largest long-distance provider in the United States.

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MCI, Inc. (formerly WorldCom and MCI WorldCom) was a telecommunications company.

Welcome to MCI. We offer Residential & Small Business Local and Long Distance, SkyTel Messaging, Prepaid Calling Services, Internet Wholesale, and Telecommunications Wholesale Services.

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Does MCI offer local phone service? MCI currently offers local phone service in several states, referred to as: "The Neighborhood, built by MCI", however new activations are no longer being offered in many locations.