Beginning Q2 2023, customers in the existing 516 area code requesting new service, an additional line, or a move in the location of their service, may be assigned a number in the new 363 area code.

The 363 area code joins 631, which in 1999 became Suffolk’s — splitting off from what was then the Long Islandwide area code of 516. Then, in 2016, Suffolk got a second area code — 934.

Since October 2021, those with a 516 area code are used to the mandatory 10-digit dialing. The new area code will have the same rules.

The local 516 will no longer be the only Nassau County area code beginning in April 2023, when a new one will start to appear in the (virtual) phonebooks.

Area code 363 will start being assigned to new phone numbers on Jan. 20, 2023. 516 has been Nassau's only area code for more than 70 years.

Starting Sunday, calls made within Nassau County's area code, 516, will all require dialing 10 digits (and depending on your carrier, 11 digits).

A new memo from the North American Numbering Plan says the 363 area code will start being assigned to phone numbers on Jan. 20, 2023. The area code will serve the same areas as 516 number holders.