Area Code Atlas

Area code 516 created for Nassau and Suffolk counties

In 1951, area code 516 was created as a new numbering plan area for Nassau and Suffolk counties, splitting from area code 914. This change established a distinct code for Long Island, New York.

NPA 516 split from 914 for Nassau and Suffolk

Area code 516 was assigned in 1951 to Nassau and Suffolk Counties in New York, splitting from 914 to accommodate growing demand for telephone numbers. This split established 516 as the area code for Nassau and Suffolk counties on Long Island.

Extraordinary NPA-Specific Conservation Procedures for 516 NPA (New York)

Geographic Split of 516 (New York) Numbering Plan Area (NPA); addition of 631 NPA

NPA 631 split from 516 for Suffolk County

Area code 631 was created on November 1, 1999, as a geographic split from 516 to serve Suffolk County, New York, due to increased demand for telephone numbers including cellular services.

Permissive dialing period for 631 begins

Permissive dialing began on April 1, 2000, allowing both area codes 516 and 631 to be used to dial numbers in the new 631 area, facilitating transition after the split.

Extended Permissive Dialing Ends for 516/631 NPAs (New York)

Mandatory ten-digit dialing implemented in area code 516

On October 24, 2021, area code 516 transitioned to mandatory ten-digit dialing. This change was required due to the nationwide designation of 988 as the three-digit code for the National Suicide Prevention Lifeline, which conflicted with existing seven-digit dialing in the area.

NPA 363 overlay on 516 announced

NPA 363 to Overlay NPA 516 (New York)

Area code 363 overlay introduced for 516

On January 20, 2023, area code 363 was announced as an overlay for area code 516 in Nassau County, New York. The overlay was implemented to provide additional numbering resources as 516 approached exhaustion.

NPA 363 announced as overlay for 516

Area code 363 was announced on January 20, 2023, as an overlay for the 516 numbering plan area. The new code was introduced to provide additional numbering resources as 516 approached exhaustion.

NPA 363 overlays 516 in Nassau County

Area code 363 was implemented as an overlay for 516 in Nassau County during the second quarter of 2023. This overlay ensured continued availability of telephone numbers in the region as 516 neared exhaustion.