Home › Connecticut › 203

203 Area Code

Area code 203 serves Bridgeport, Stamford, New Haven, Waterbury, Norwalk and nearby communities in Connecticut. It has been in service since January 1, 1947.

StateConnecticut
Time zoneEastern
Local time now…
Prefixes in use778
Overlay with475
Projected to run out2055
BridgeportStamfordNew HavenWaterburyNorwalkDanburyMeridenWest HavenMilfordSheltonNaugatuckEast HavenNorth HavenAnsoniaWallingford CenterGreenwichOrangeDerbyBethelTrumbull CenterSandy HookRiversideLong HillCos CobRidgefieldNew CanaanStaplesOld GreenwichNorthfordBranford CenterCheshire VillageDaniels FarmNorotonByramBridgeportStamfordNew HavenWaterbury
Cities and towns served by area code 203

Who issues 203 numbers

Mobile 21%VoIP and cable 22%Landline 58%

Share of the 778 prefixes (the three digits after 203) assigned to each type of carrier. Classification by carrier name, approximate.

CarrierPrefixes
Frontier332
Verizon Wireless61
AT&T Mobility52
T-Mobile47
Verizon Business (MCImetro)41
Lumen (Level 3)41
Paetec Itel40
AT&T (Teleport)33

Cities and towns in area code 203

CityPopulationOther area codes
Bridgeport152,273475
Stamford139,535475
New Haven138,774475
Waterbury115,771475
Norwalk94,508475
Danbury89,033475
Meriden60,810475
West Haven55,351475
Milford51,215475
Shelton42,880475
Naugatuck32,230475
East Haven27,729475
North Haven24,177475
Ansonia19,216475
Wallingford Center18,107475
Greenwich14,528475
Orange14,251475
Derby12,925475
Bethel11,606475
Trumbull Center10,137475
Sandy Hook9,718475
Riverside9,216475
Long Hill8,597475
Cos Cob7,354475
Ridgefield7,103475
New Canaan7,032475
Staples6,985475
Old Greenwich6,904475
Northford6,161475
Branford Center6,130475
Cheshire Village6,049475
Daniels Farm5,995475
Noroton5,522475
Byram5,011475

Got a call from 203?

A 203 number was originally issued in Connecticut, but that does not prove the caller is there. 22% of 203 prefixes belong to VoIP and cable providers, whose numbers can be bought online and used from anywhere. Caller ID can also be spoofed, so treat urgent requests for money, codes or passwords from any area code with suspicion, and call back on a number you already know.

All 778 prefixes in area code 203

Format: (203) XXX-YYYY. Carrier is the company the block was originally assigned to; numbers may since have been ported to another carrier.

Questions about area code 203

Where is area code 203?
Area code 203 is in Connecticut. It covers Bridgeport, Stamford, New Haven, Waterbury, Norwalk, Danbury and 28 more cities and towns.
What time zone is area code 203?
Area code 203 is in the Eastern time zone.
Is 203 a toll-free number?
No. 203 is a geographic area code in Connecticut. Toll-free numbers in the US start with 800, 833, 844, 855, 866, 877 or 888.
Why does 203 share its area with 475?
203 and 475 form an overlay: they cover the same territory, so new numbers there can get any of these codes, and local calls need all 10 digits.
Will area code 203 run out of numbers?
NANPA's latest forecast projects the 203/475 overlay to exhaust in the fourth quarter of 2055. Before that happens, a new area code is usually added as an overlay; existing numbers keep their code.

Other area codes in Connecticut