Parts of Long Island could soon see a new area code and 10-digit dialing as the existing supply of telephone numbers quickly dwindles.

A state agency this week proposed splitting up Suffolk County between the existing 631 area code and a new area code.

New York’s Department of Public Service said another proposal would keep all existing 631 numbers while using the additional area code for new numbers.

The department said the 631 area code has about 65,000 assignable numbers left and is expected to run out by early 2016.

A plan to implement a new area code could be in place by fall.

The 631 area code was split off from 516 in 1999.

That area code, now serving only Nassau County, is expected to hit capacity in 2020.

(AP)