301 area code — Washington, MD geographic
- State
- Maryland
- Major area
- Washington
- Time zone
- Eastern
- In service since
- 1947-01-01
- Active prefixes
- 784
- Rate centers
- 64
- Carriers
- 31
- Projected exhaust
- 1Q 2041
301 is the area code for Washington, Maryland, in service since January 1, 1947, Eastern time. Together with 240, 227 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 784 active NXX prefixes in 301, assigned to 31 carriers. 397 of those prefixes are pooled — shared between carriers in thousands-number blocks. The code spans 64 rate centers (billing localities).
If a 301 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.
Among Maryland codes, 301 stands out as the oldest area code in Maryland, in service since 1947.
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.
Later relief produced 410 (1991), 240 (1997), 227 (2023) from its territory.
Largest localities in 301
| Locality (rate center) | Active prefixes | Also served by |
|---|---|---|
| Washington Zone 03 | 112 | 227, 240 |
| Washington Zone 02 | 88 | 227, 240 |
| Washington 236 Zone 13 | 53 | 227, 240 |
| Washington Zone 10 | 52 | 227, 240 |
| Washington Zone 04 | 47 | 227, 240 |
| Frederick | 37 | 227, 240 |
| Washington Zone 05 | 37 | 227, 240 |
| Gaithersburg | 33 | 227, 240 |
| Washington Zone 11 | 30 | 227, 240 |
| Waldorf | 25 | 227, 240 |
FAQ
Will 301 run out of numbers?
NANPA's current forecast projects exhaust in 1Q 2041 — decades of capacity remain.
Why am I getting spam calls from 301 numbers?
Scammers spoof recognizable area codes so calls look local or familiar. A displayed 301 number does not prove the call originated there — see our guide to spotting spoofed calls.
Where is a 301 number from?
301 is assigned to Washington and surrounding areas of Maryland in the Eastern time zone. The three digits after the area code (the prefix) narrow it down to a rate center.
Is 301 a toll-free number?
No. 301 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 240 and 301 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.