Area codes 631 and 934

The red area is area code 631; the blue area is the rest of New York State.

Area code 631 is the telephone area code for Suffolk County, New York; it covers eastern and central parts of Long Island. 631 was created in 1999 as a split from area code 516. Population centers within 631 include Babylon, Brookhaven, Huntington, Patchogue, Smithtown, Shelter Island, and the Hamptons.

An overlay area code (934) will become effective in the existing plan area 631, effective in 2016. This will be the first overlay for New York state outside New York City and will require 10-digit dialing for both area codes.

History of Suffolk County area codes

1947–1951: 914

With the introduction of the North American Numbering Plan in October 1947, Suffolk, Nassau, and the lower Hudson Valley were assigned area code 914.

1951–1999: 516

In 1951, the 516 area code was assigned to Nassau and Suffolk.

1999–present: 631

On November 1, 1999, 516 was reduced to Nassau County, while 631 was created for Suffolk County. Permissive dialing for numbers in 516 across Long Island continued until the spring of 2000.

Future

According to the October 2014 NPA Exhaust Projection, area code 631 is expected to be exhausted in the third quarter of 2016, by which time an additional area code will be required for Suffolk County. An overlay with the future area code 934 was announced in December 2014.

See also

• List of New York area codes
• List of NANP area codes
• North American Numbering Plan

New York area codes: 212, 315, 332, 347, 516, 518, 585, 607, 631, 646, 680, 716, 718, 845, 914, 917, 929, 934
	North: 203, 401, 860, 959
West: 516	area code 631/934	East: Atlantic Ocean
	South: Atlantic Ocean
Connecticut area codes: 203, 475, 860, 959
Rhode Island area codes: 401

External links

• NANPA Area Code Map of New York