Every ZIP code in the United States, with weather, radar, trivia and the numbers behind it. Five digits since 1963!

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zipcodes.pro — AREA-CODE/443

443 area code

Area code 443 is in Maryland. It covers Baltimore, Columbia, Ellicott City and 284 other places: 284 ZIP codes in Baltimore County, Anne Arundel County, Baltimore city and 17 others. Local time there is , Eastern Time. In service since 1997 as an overlay: it covers the same area as 410 and 667, so a number from there can have any of them.

Time zone
Eastern
Largest city
Baltimore
Overlays
410, 667
In service since
1997
Rate centres
81
Prefixes assigned
785 (7,850,000 numbers)

Who calls from a 443 number

NANPA records the carrier each block of 443 numbers is assigned to. Of the 7.8 million 443 numbers assigned, 49% are with cable, internet-calling, business and other carriers (PAETEC (Windstream), Onvoy and Bandwidth); 46% with mobile carriers (T-Mobile, Verizon Wireless and AT&T Mobility); 5% with local phone 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 443 numbers
CarrierKindShare
T-MobileMobile20%
Verizon WirelessMobile14%
AT&T MobilityMobile12%
PAETEC (Windstream)Cable, VoIP, other9%
OnvoyCable, VoIP, other7%
BandwidthCable, VoIP, other6%

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 443

The 71 places with a telephone rate centre of their own using 443, largest first. Each links to its ZIP codes.

Places in area code 443
PlaceZIP codesPopulation
Baltimore, MD 42 573,243
Columbia, MD 3 104,338
Ellicott City, MD 3 75,257
Glen Burnie, MD 3 72,590
Dundalk, MD 1 65,969
Towson, MD 5 58,679
Severn, MD 1 58,402
Odenton, MD 1 45,002
Catonsville, MD 1 43,368
Annapolis, MD 8 40,720
Essex, MD 1 40,580
Severna Park, MD 1 40,228
Randallstown, MD 1 35,957
Pikesville, MD 2 33,524
Salisbury, MD 4 33,285
Parkville, MD 1 30,549
Crofton, MD 1 29,549
Elkridge, MD 1 26,283
Reisterstown, MD 1 25,582
Edgewood, MD 1 24,922
Cockeysville, MD 1 23,962
Arbutus, MD — 22,507
Westminster, MD 2 20,445
Millersville, MD 1 18,643
Easton, MD 1 17,308
Aberdeen, MD 1 17,298
Elkton, MD 2 15,910
Cambridge, MD 1 13,152
Bel Air, MD 2 10,585
Fallston, MD 1 10,013
Sparrows Point, MD 1 9,565
Stevensville, MD 1 8,802
Taneytown, MD 1 7,932
Parkton, MD 1 7,440
Ocean City, MD 2 6,903
Sparks Glencoe, MD 1 6,459
Hampstead, MD 1 6,251
Chestertown, MD 2 5,594
Berlin, MD 1 5,232
Denton, MD 1 4,936
Centreville, MD 1 4,761
Sykesville, MD 1 4,491
Perryville, MD 1 4,447
Pocomoke City, MD 1 4,405
Delmar, MD 1 4,261
Glenwood, MD 1 3,696
Princess Anne, MD 1 3,569
Churchville, MD 1 3,103
Prince Frederick, MD 1 2,955
Federalsburg, MD 1 2,837
Snow Hill, MD 1 2,659
Jarrettsville, MD 1 2,560
Crisfield, MD 1 2,499
Solomons, MD 1 2,440
North Beach, MD 1 2,296
West River, MD 1 2,211
New Windsor, MD 1 1,400
Willards, MD 1 1,280
Trappe, MD 1 1,055
Union Bridge, MD 1 1,055
Queenstown, MD 1 907
Sharptown, MD 1 874
Chesapeake City, MD 1 810
Bishopville, MD 1 516
Port Deposit, MD 1 491
Nanticoke, MD 1 434
Vienna, MD 1 382
Darlington, MD 1 353
Sherwood, MD 1 229
Fork, MD 1 172
Chase, MD 1 —

Nearby places using 443

These places have no rate centre of their own in NANPA's records; the nearest one uses 443. Near an area-code boundary that can be wrong for part of a town.

ZIP codes in area code 443

284 ZIP codes in 205 towns, by the town each is mailed to, largest first. Each links to its own page.

Where 443 numbers are issued

NANPA's rate centres with the most 443 prefixes (each prefix is 10,000 numbers), under NANPA's own abbreviated names.

Rate centres using area code 443
Rate centrePlacePrefixes
BALTIMORE Baltimore 185
ANNAPOLIS Annapolis 39
TOWSON Towson 33
COLUMBIA Columbia 31
GLENBURNIE Glen Burnie 26
CATONSVL Catonsville 22

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 443

Where is area code 443?

Area code 443 is in Maryland. It covers Baltimore, Columbia, Ellicott City and 284 other places: 284 ZIP codes in Baltimore County, Anne Arundel County, Baltimore city and 17 others.

What ZIP codes are in area code 443?

284 ZIP codes, by the town each is mailed to: Baltimore (42, 21201 to 21298), Columbia (3, 21044 to 21046), Ellicott City (3, 21041 to 21043), Glen Burnie (3, 21060 to 21062) and 201 more towns. The full list is on this page.

What time zone is area code 443 in?

Eastern time.

Is a 443 number a mobile or a landline?

It can be either. 46% of 443 numbers are assigned to mobile carriers and 5% 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 443?

410 and 667. They cover the same area as 443, so a new number there can be given any of them.

Does a 443 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 443 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 443.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/area-code/443

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