List of original NANP area codes

204 is one of the original 86 area codes assigned in 1947 in the contiguous United States and the then-nine-province extent of Canada.

This included a three-digit central office prefix, dialed as the first two letters of the local central office name and one digit, and the four-digit subscriber station number.

In the 1940s, the Bell System developed the North American Numbering Plan, a system of initially 86 allocated area codes which were used at first only by switchboard operators to route trunk calls between plan areas.

The area code was one of the original area codes established in October 1947 by AT&T in the North American Numbering Plan (NANP).

In preparation for direct distance dialing, AT&T and the Bell System developed the North American Numbering Plan in the 1940s.

Originally only 86 area codes were assigned.

Area code 214 was one of the original area codes established with the North American Numbering Plan in October 1947.

Area code 201 was the first-assigned numbering plan area (NPA) code of the original NPAs when AT&T devised the North American Numbering Plan in 1947.

Area code 212 is one of the original 86 area codes assigned by AT&T in 1947, when it served the entire five boroughs of New York City until 1984.

It was one of the original area codes issued in the North American Numbering Plan on January 1, 1947.

217 was one of the original area codes, which were created in 1947.

In 1947, when AT&T established the North American Numbering Plan, the original area code 215 included the entire southeastern part of the Commonwealth, from the Delaware border to the Lehigh Valley.

Area code 305 was one of the original area codes created in 1947, and originally covered the entire state of Florida.

Area code 206 was one of the original area codes assigned in 1947, and originally covered the entire state of Washington.

Area code 301 was one of the original area codes established in 1947 when the North American Numbering Plan (NANP) was created, and originally covered the entire state of Maryland.

Area code 404 was created in 1947 as one the original numbering plan areas in North America.

Area code 303 was one of the original area codes put into service in 1947, and originally covered the entire state of Colorado.

The main area code, 416, was one of the 86 original area codes introduced in 1947.

518 was established as one of the original area codes in 1947.

Area code 503 was one of the original area codes created as part of the North American Numbering Plan by AT&T and Bell Laboratories in 1947.

Area code 512 was one of the original area codes established in October 1947.

Area code 207 was created as one of the original area codes in 1947.

The main area code, 601, was one of the original area codes implemented in 1947, and covered the entire state of Mississippi.

The main area code, 315, was one of the original area codes created in 1947.

613 is one of the 86 original area codes in the NANP assigned in October 1947.

317 was one of the original area codes introduced in 1947.

504 was one of the original area codes created in 1947, and originally covered all of Louisiana.