Area code 931

North American area code 931 is a Tennessee telephone area code for Middle Tennessee, United States. Area code 931 is assigned to a horseshoe-shaped region of 28 Middle Tennessee counties, comprising essentially all of Middle Tennessee except for the Nashville metropolitan area.

The 931 area code was created in 1997 from area code 615, which had previously covered almost all of Middle Tennessee, but afterwards was restricted to Nashville and immediately surrounding counties. Area code 931 began operation on September 15, 1997; permissive dialing continued until January 15, 1998.

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