What is 314 area code?

The 314 area code is a telephone area code in the North American Numbering Plan (NANP) for the city of St. Louis, Missouri, and most of its inner suburbs. It was one of the original 86 area codes created in 1947.

The 314 area code is an enclave, completely surrounded by the 636 area code, which serves most of the outer suburbs of St. Louis. This makes 314 one of the smallest area codes in geographic area that is not a non-contiguous area code (like those serving island territories). Due to increasing demand, an overlay area code, 557, has been assigned for the same area and was activated in August 2022. This means that 10-digit dialing is now required in the 314 area.