Maryland area codes

Maryland has 6 area codes covering 2 areas. In 2 of them several codes overlay the same ground, so a number there can have any of them: 410, 443 and 667 around Baltimore; 227, 240 and 301. The newest, 227, came into service in 2023.

Area codes: 6
Areas: 2
Overlay areas: 2
Time zone: Eastern
Newest: 227 (2023)
ZIP codes: 605 in Maryland

Somewhere in Maryland now? What area code am I in? answers from your location.

Every Maryland area code

Area codes in Maryland
Code	Where	Overlays	Since
227	Frederick County, Montgomery County	240, 301	2023
240	Frederick County, Montgomery County	227, 301	1997
301	Frederick County, Montgomery County	227, 240	1947
410	Baltimore, Columbia, Ellicott City	443, 667	1991
443	Baltimore, Columbia, Ellicott City	410, 667	1997
667	Baltimore, Columbia, Ellicott City	410, 443	2012

Maryland area codes by area

Codes that overlay one another share one area. The places listed have a telephone rate centre of their own in NANPA's records, largest first; each links to its ZIP codes.

410, 443, 667 — Baltimore

410 (1991) was here first; 443 (1997) and 667 (2012) overlay it, so a number from anywhere in the area can have any of them.

91 places, the largest 36 here (all of them on 410):

9 counties:

301, 240, 227 — Frederick County

301 (1947) was here first; 240 (1997) and 227 (2023) overlay it, so a number from anywhere in the area can have any of them.

8 counties:

Area codes of the largest cities in Maryland

Largest cities in Maryland and their area codes
City	Area codes	Population
Baltimore	410, 443, 667	573,243
Columbia	443, 410, 667	104,338
Germantown †	240, 301, 227	90,719
Frederick	240, 301, 227	83,395
Waldorf	240, 301, 227	82,943
Ellicott City	410, 443, 667	75,257
Glen Burnie	410, 443, 667	72,590
Gaithersburg	240, 301, 227	69,825
Bethesda †	240, 301, 227	69,397
Rockville †	240, 301, 227	67,671
Dundalk	443, 410, 667	65,969
Towson	410, 443, 667	58,679
Severn	410, 443, 667	58,402
Bel Air South †	443, 410, 667	58,137
Aspen Hill †	240, 301, 227	53,279
Wheaton †	240, 301, 227	52,926
North Bethesda †	240, 301, 227	49,677
Gwynn Oak †	410, 443, 667	47,099
Potomac †	240, 301, 227	45,902
Odenton	667, 410, 443	45,002
Hagerstown	240, 301, 227	43,665
Catonsville	410, 443, 667	43,368
Annapolis	443, 410, 667	40,720
Essex	443, 410, 667	40,580
Woodlawn †	410, 443, 667	40,379
Severna Park	410, 443, 667	40,228
Nottingham †	410, 443, 667	39,514
Lutherville Timonium †	410, 443, 667	39,100
Clinton †	240, 301	38,376
Windsor Mill †	443, 410, 667	38,208
Owings Mills †	443, 410, 667	37,245
Randallstown	443, 410, 667	35,957
Olney †	240, 301, 227	35,797
Halethorpe †	410, 443, 667	34,907
Pasadena †	410, 443, 667	34,309
Montgomery Village †	240, 301, 227	34,110
Brooklyn †	410, 443, 667	34,062
Pikesville	667, 443, 410	33,524
Salisbury	410, 667, 443	33,285
Middle River †	443, 667, 410	31,712

† NANPA lists no rate centre for the town itself; these are the codes of the nearest one. A town on an area-code boundary can differ from its neighbour.

Questions about Maryland area codes

How many area codes does Maryland have?

6: 227, 240, 301, 410, 443 and 667. All of them are in overlay areas, where several codes share the same ground.

What is the newest area code in Maryland?

227, in service since 2023. It overlays 240 and 301.

What are the area codes of the largest cities in Maryland?

Baltimore: 410, 443 and 667. Columbia: 443, 410 and 667. Germantown: 240, 301 and 227. Frederick: 240, 301 and 227. Waldorf: 240, 301 and 227.

What time zone are Maryland area codes in?

Eastern time.

Every US area code · Maryland ZIP codes

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

Cite this page

zipcodes.pro. “Maryland area codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/area-codes/md

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