631 Area Code
Suffolk County, Long Island, New York
Area code 631 is located in Suffolk County, Long Island, New York. It covers Huntington, Islip, and surrounding areas in the Eastern time zone (UTC-5). Administered by NANPA.
Where is area code 631?
Area code 631 is located in Suffolk County, Long Island, New York. It covers Huntington, Islip, and surrounding areas in the Eastern time zone (UTC-5).
Area code 631 is overlaid by area code 934. Both codes serve the same geographic region and require 10-digit dialing for local calls.
Cities Covered by Area Code 631
Area code 631 primarily serves the Suffolk County, Long Island area of New York. The exact coverage includes Huntington, Islip, and Brookhaven, along with surrounding communities and suburbs.
Time Zone
Eastern Time — UTC-5
Area code 631 operates in the Eastern Time Zone. When calling 631 numbers from a different time zone, be sure to account for the time difference to reach people during business hours.
About Area Code 631
Area code 631 was introduced in 1999 as a geographic area code serving Suffolk County, Long Island, New York. As demand for phone numbers grew, overlay code 934 was added to the same region, requiring 10-digit dialing for local calls. Area codes are administered by NANPA (North American Numbering Plan Administration), the organization responsible for managing phone number resources in the US and Canada.