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zipcodes.pro — AREA-CODE/301

301 area code

Area code 301 is in Maryland. Local time there is , Eastern Time. In service since 1947; 227 (2023) and 240 (1997) overlay it, so a number from there can have any of them.

Time zone
Eastern
Overlays
227, 240
In service since
1947
Rate centres
64
Prefixes assigned
784 (7,840,000 numbers)

Who calls from a 301 number

NANPA records the carrier each block of 301 numbers is assigned to. Of the 7.8 million 301 numbers assigned, 51% are with local phone companies (Verizon); 24% with cable, internet-calling, business and other carriers (Onvoy and Bandwidth); 24% with mobile carriers (Verizon Wireless, T-Mobile and AT&T Mobility); 1% with paging companies.

That is who the numbers were assigned to: people keep their number when they change carrier, so any one number may have moved since.

Carriers holding the most 301 numbers
CarrierKindShare
VerizonLandline50%
Verizon WirelessMobile8%
T-MobileMobile8%
AT&T MobilityMobile6%
OnvoyCable, VoIP, other4%
BandwidthCable, VoIP, other4%

An area code says where a number was issued, not where the caller is: people keep their numbers when they move, and caller ID can be set to show any number, which the FCC calls spoofing. If a call you did not expect asks for money or personal details, the FCC advises hanging up and calling the company back on a number you look up yourself. Unwanted calls can be reported to the FTC at ReportFraud.ftc.gov.

Places in area code 301

The 39 places with a telephone rate centre of their own using 301, largest first. Each links to its ZIP codes.

Places in area code 301
PlaceZIP codesPopulation
Frederick, MD 6 83,395
Waldorf, MD 4 82,943
Gaithersburg, MD 9 69,825
Hagerstown, MD 6 43,665
Cumberland, MD 5 18,804
Brandywine, MD 1 12,160
La Plata, MD 1 10,683
Mount Airy, MD 1 9,805
Brunswick, MD 1 8,450
Frostburg, MD 1 6,977
Walkersville, MD 1 6,414
Thurmont, MD 1 6,254
Poolesville, MD 1 5,764
Middletown, MD 1 5,014
Leonardtown, MD 1 4,808
Indian Head, MD 1 4,055
Smithsburg, MD 1 3,115
Emmitsburg, MD 1 2,845
Myersville, MD 1 2,358
Oakland, MD 1 2,254
Nanjemoy, MD 1 2,129
Hughesville, MD 1 2,098
Williamsport, MD 1 1,949
Hancock, MD 1 1,625
New Market, MD 1 1,603
Westernport, MD 1 1,588
Flintstone, MD 1 1,404
Mechanicsville, MD 1 1,395
Buckeystown, MD 1 1,192
Keedysville, MD 1 1,183
Highfield-Cascade, MD — 1,089
Grantsville, MD 1 1,013
Lonaconing, MD 1 889
Mount Savage, MD 1 514
Friendsville, MD 1 416
McCoole, MD — 373
Clear Spring, MD 1 342
Kitzmiller, MD 1 264
Bittinger, MD 1 —

Nearby places using 301

These places have no rate centre of their own in NANPA's records; the nearest one uses 301. Near an area-code boundary that can be wrong for part of a town.

ZIP codes in area code 301

189 ZIP codes in 135 towns, by the town each is mailed to, largest first. Each links to its own page.

Where 301 numbers are issued

NANPA's rate centres with the most 301 prefixes (each prefix is 10,000 numbers), under NANPA's own abbreviated names.

Rate centres using area code 301
Rate centrePlacePrefixes
WSHNGTNZN3 — 112
WSHNGTNZN2 — 88
WSNG236Z13 — 53
WSNGTNZN10 — 52
WSHNGTNZN4 — 47
FREDERICK Frederick 37

Counties

The counties of its ZIP codes, most residents first, with how many of its ZIP codes each has.

Which code covers where you are now? What area code am I in? answers from your location.

Questions about area code 301

Where is area code 301?

Area code 301 is in Maryland.

What ZIP codes are in area code 301?

189 ZIP codes, by the town each is mailed to: Germantown (3, 20874 to 20876), Frederick (6, 21701 to 21709), Waldorf (4, 20601 to 20604), Gaithersburg (9, 20877 to 20899) and 131 more towns. The full list is on this page.

What time zone is area code 301 in?

Eastern time.

Is a 301 number a mobile or a landline?

It can be either. 24% of 301 numbers are assigned to mobile carriers and 51% to local phone companies (NANPA, 2026-10-10); the rest are with cable, internet-calling, business and paging carriers. A number keeps its area code when it moves to another carrier.

What area codes overlay 301?

227 and 240. They cover the same area as 301, so a new number there can be given any of them.

Does a 301 number mean the caller is in Maryland?

Not necessarily. An area code says where the number was first issued. People keep their numbers when they move or switch carriers, and calling software can show any number, so a 301 call can come from anywhere.

Other area codes in Maryland

All 6 Maryland area codes, by area, with the cities each covers

Source: NANPA NPA database, central office code and thousands-block assignments, 2026-10-10. Places are matched to NANPA's rate centres by name; see sources.

Cite this page

zipcodes.pro. “Area code 301.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/area-code/301

Underlying data is public domain or openly licensed — sources, vintages and licences.