Area code 314

Area code 314 serves the independent city of St. Louis, Missouri including some of its suburbs in neighboring St. Louis County. Most of the suburbs in area code 314 are to the northwest or west-central from the city's core.

314 is surrounded by the overlay area code 636 and a southern area code 573 which runs outside of the 636 overlay. Both of these area codes are totally within Missouri. Across the Mississippi River in Illinois, 314 is bordered by area code 618 making up the Metro East.

All of 314, all of 636, a large part of 618 in Illinois, a portion of area code 573, and a small portion of the southern area of area code 217 in Illinois, north of area code 618, are components of the Greater St. Louis metropolitan area.

Area code 314 was one of the original area codes created in October 1947. It originally covered most of the eastern half of Missouri, from the Illinois border to Jefferson City. It stretched along nearly the entire width of the state along the Mississippi River. It was split on January 7, 1996, when most of the western and southern portion was assigned to area code 573, leaving 314 to cover most of the immediate St. Louis metropolitan area.

The creation of 573 was intended to be a long-term solution. Within only two years, however, 314 was close to exhaustion once again due to the proliferation of cell phones, fax machines and pagers in the St. Louis core. The supply of numbers was further limited because the St. Louis LATA extends across much of the southern portion of Illinois, meaning several numbers that were part of Illinois' 618 weren't available for use. As a result, 314 was reduced to its current size on May 22, 1999, when area code 636 was assigned to St. Louis' outer western suburbs. Before the introduction of number portability, 314 was used for all cell phones on the Missouri side of the St. Louis area.

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