RSA (Rural Service Area)

A geographic area of population defined by the United States Census Bureau.

RSAs identify areas that are not within an MSA (Metropolitan Statistical Area). All counties in the country are within either an MSA or RSA.

MSAs and RSAs are the divisions that were used by the FCC to geographically separate cellular radio frequency (spectrum) licenses that were granted to wireless (cell phone) carriers in the 1980s. 

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