Map of the Original Area Code Assignments in 1947

LincMad map of 1947 area codes, map1947.svg
Looking for a current map of U.S. & Canada area codes? Go to LincMad’s 2020 Area Code & Time Zone Map!

Highlights:

This map shows the original area code boundaries, established in 1947. Customer direct-dialed long distance did not yet exist, but area codes facilitated operator-dialed calls. Notice that in all cases where a state or province has a single area code, the middle digit is always ‘0’, while area codes in states and provinces with multiple area codes all have a ‘1’ as the middle digit. Area codes were not yet assigned for areas such as Alaska, Hawaii, northern Canada, and the Caribbean. In 1947, Newfoundland and Labrador had not yet joined Canada, but they were included in the original area code 902 (at that time, New Brunswick, Nova Scotia, and Prince Edward Island, plus what was then the U.K. dominion of Newfoundland); in 1955, New Brunswick and Newfoundland & Labrador left to form the new 506 area code, and in 1962 Newfoundland & Labrador split to form the current area code 709.

A number of these original area codes split not long after they were established, beginning in 1948 with the creation of area code 219 in northern Indiana. Other area code boundaries were significantly realigned in areas like Minnesota, California, and Massachusetts. The separation of N0X area codes for single-code states and N1X area codes for multi-code states, however, did not survive very long, with the assignment of area code 813 in southern Florida in 1953 marking the first of many that violated the rule. However, it remained true until 1995 that the middle digit of any area code was always a ‘0’ or a ‘1’, at which point area codes with a middle digit of ‘2’ through ‘8’ began being assigned. (Area codes with middle digit ‘9’ are reserved for expansion to longer telephone numbers, some time in the 21st Century.)