240 area code — Washington, MD geographic

Data: NANPA public reports, current as of July 28, 2026.

State
Maryland
Major area
Washington
Time zone
Eastern
In service since
1997-06-01
Split from
301
Overlay complex
227 / 240 / 301
Active prefixes
785
Rate centers
63
Carriers
44
Projected exhaust
1Q 2041

240 is the area code for Washington, Maryland, in service since June 1, 1997, Eastern time. Together with 227, 301 it forms the 227/240/301 overlay. Because of number portability and VoIP, the area code tells you where the number was issued, not where the caller is right now.

NANPA lists 785 active NXX prefixes in 240, assigned to 44 carriers. 727 of those prefixes are pooled — shared between carriers in thousands-number blocks. The code spans 63 rate centers (billing localities).

If a 240 call asks for money or personal data, treat the displayed number as unverified: hang up and reach the organization through its published number. Numbering data locates numbers, not callers.

The dialing plan is 10D for home-NPA local calls and 10D across codes.

Official projections put exhaust for the 227/240/301 complex at 1Q 2041.

Its parent code is 301, which it left in 1997.

Largest localities in 240

Largest rate centers in area code 240
Locality (rate center)Active prefixesAlso served by
Washington Zone 03 73 227, 301
Washington Zone 02 64 227, 301
Washington Zone 10 54 227, 301
Frederick 43 227, 301
Gaithersburg 40 227, 301
Laurel 236 39 227, 301
Hagerstown 33 227, 301
Washington Zone 04 30 227, 301
Washington Zone 05 28 227, 301
Waldorf 26 227, 301

FAQ

Is 240 a toll-free number?

No. 240 is a geographic code; calls are billed like any other domestic call. Toll-free codes are 800, 833, 844, 855, 866, 877 and 888.

Why do 227 and 240 cover the same place?

They are overlays: when a code runs low on numbers, a new code is added over the same territory instead of splitting it. The 227/240/301 complex shares one service area, and local calls are dialed with 10 digits.

Will 240 run out of numbers?

NANPA's current forecast projects exhaust in 1Q 2041 — decades of capacity remain.

Why am I getting spam calls from 240 numbers?

Scammers spoof recognizable area codes so calls look local or familiar. A displayed 240 number does not prove the call originated there — see our guide to spotting spoofed calls.