City of license

In American, Canadian and Philippine broadcasting, a city of license or community of license is the community that a radio station or television station is officially licensed to serve by that country's broadcast regulator.

In North American broadcast law, the concept of community of license dates to the early days of AM radio broadcasting. The requirement that a broadcasting station operate a main studio within a prescribed distance of the community which the station is licensed to serve appears in U.S. law as early as 1939.

Various specific obligations have been applied to broadcasters by governments to fulfill public policy objectives of broadcast localism, both in radio and later also in television, based on the legislative presumption that a broadcaster fills a similar role to that held by community newspaper publishers.

In the United States, the Communications Act of 1934 requires that “the Commission shall make such distribution of licenses, frequencies, hours of operation, and of power among the several States and communities as to provide a fair, efficient, and equitable distribution of radio service to each of the same.” The Federal Communications Commission interprets this as requiring that every broadcast station “be licensed to the principal community or other political subdivision which it primarily serves.” For each broadcast service, the FCC defines a standard for what it means to serve a community; for example, commercial FM radio stations are required to provide an electric field of at least 3.16 millivolts per meter (mV/m) over the entire land area of the community, whereas non-commercial educational FM stations need only provide a field strength of 1 mV/m over 50% of the community's population. This electric field contour is called the “principal community contour”.

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