Area Code 203 Information
| Area Code | 203 |
| Population | 146866 |
| Type of Code: | General Purpose Code |
| Geographic(G) or non-geographic(N): | G |
| Is this code assigned: | Yes |
| Is this code in use: | Y |
| In service date: | 1947-01-01 |
| Planning Letter(s): | 388 255 217 138 |
| Location: | CT |
| Country: | US |
| Time Zone: | E |
| Parent NPA: |
Introduced as one of the original 86 area codes in 1947, area codes 203 originally covered Connecticut. Over time, as the population grew and the demand for phone numbers increased, Connecticut had to undergo area code splits to accommodate the increasing requirement. In 1995, the state was divided into two area codes, with area code 860 taking over the northern and central regions, while area code 203 continued to serve the southwest part of Connecticut, including the New Haven and Bridgeport metropolitan areas. Today, area code 203 has an overlay plan with area code 475 to accommodate the increasing number of phone numbers demands.
Geographical Coverage
Area code 203 covers the southwest part of Connecticut and is associated with the following cities and towns:
1. New Haven
2. Bridgeport
3. Stamford
4. Norwalk
5. Waterbury
6. Danbury
7. Westport
8. Milford
9. Fairfield
10. Greenwich
11. Hamden
12. Meriden
13. Shelton
14. Stratford
15. Trumbull
Demographics and Population
The region covered by area code 203 is diverse, both in terms of demographics and population. According to the United States Census Bureau, the combined population of the major cities under area code 203 is over 1.2 million. The largest city within the region is Bridgeport, with a population of more than 143,000, closely followed by New Haven, with over 130,000 residents.
The racial and ethnic composition of area code 203 is notably diverse. According to data from the United States Census Bureau, the racial composition of the ten most populous cities within area code 203 is:
- White: 63.04%
- Black or African American: 18.57%
- Asian: 5.68%
- Other races: 11.49%
The Hispanic or Latino population also constitutes an estimated 23.4% of the total population.
Education, Economy, and Employment
Area code 203 benefits from access to many higher education institutions within and around the region. These include Yale University in New Haven and the University of Bridgeport. The education sector significantly contributes to the region's economy and employment.
The cities within area code 203 have diverse economies, with some key industries being healthcare, manufacturing, finance, and retail. Regional employers include Yale-New Haven Hospital, Sikorsky Aircraft, and Boehringer Ingelheim Pharmaceuticals.
Zip Codes
Some of the principal zip codes falling under area code 203 include:
- Bridgeport: 06601 to 06610
- New Haven: 06501 to 06540
- Stamford: 06901 to 06928
- Norwalk: 06850 to 06860
- Waterbury: 06701 to 06726
- Danbury: 06810 to 06817
Area code 203, Connecticut's original area code, has a fascinating history and diverse demographics. Covering important cities such as Bridgeport and New Haven, the region benefits from access to prestigious educational institutions and a vibrant economy. Today, with area code 475, 203 continues to serve the southwest region of Connecticut and is a significant part of the United States telephone numbering plan.
Area Code Zipcodes
| Zipcode | City | State |
| 6401 | ANSONIA | Connecticut |
| 6403 | BEACON FALLS | Connecticut |
| 6404 | BOTSFORD | Connecticut |
| 6405 | BRANFORD | Connecticut |
| 6408 | CHESHIRE | Connecticut |
| 6408 | MACYS BY MAIL | Connecticut |
| 6410 | CHESHIRE | Connecticut |
| 6411 | BLOOMINGDALES BY MAIL LTD | Connecticut |
| 6411 | CHESHIRE | Connecticut |
| 6418 | DERBY | Connecticut |
| 6437 | GUILFORD | Connecticut |
| 6440 | HAWLEYVILLE | Connecticut |
| 6443 | MADISON | Connecticut |
| 6450 | MERIDEN | Connecticut |
| 6451 | MERIDEN | Connecticut |
| 6460 | MILFORD | Connecticut |
| 6461 | MILFORD | Connecticut |
| 6468 | MONROE | Connecticut |
| 6468 | STEPNEY | Connecticut |
| 6468 | UPPER STEPNEY | Connecticut |
| 6470 | NEWTOWN | Connecticut |
| 6471 | N BRANFORD | Connecticut |
| 6471 | NORTH BRANFORD | Connecticut |
| 6472 | NORTHFORD | Connecticut |
| 6473 | NO HAVEN | Connecticut |
| 6473 | NORTH HAVEN | Connecticut |
| 6477 | ORANGE | Connecticut |
| 6478 | OXFORD | Connecticut |
| 6478 | SEYMOUR | Connecticut |
| 6482 | SANDY HOOK | Connecticut |
| 6483 | SEYMOUR | Connecticut |
| 6484 | HUNTINGTON | Connecticut |
| 6484 | SHELTON | Connecticut |
| 6487 | SOUTH BRITAIN | Connecticut |
| 6488 | SOUTHBURY | Connecticut |
| 6491 | STEVENSON | Connecticut |
| 6492 | WALLINGFORD | Connecticut |
| 6492 | YALESVILLE | Connecticut |
| 6493 | CT GEN MED CLAIMS OFFICE | Connecticut |
| 6493 | PUBLISHERS CLEARING HOUSE | Connecticut |
| 6493 | WALLINGFORD | Connecticut |
| 6494 | FOSDICK CORP | Connecticut |
| 6494 | WALLINGFORD | Connecticut |
| 6495 | INTERNATIONAL MASTERS PUB | Connecticut |
| 6495 | WALLINGFORD | Connecticut |
| 6501 | N HAVEN | Connecticut |
| 6501 | NEW HAVEN | Connecticut |
| 6502 | N HAVEN | Connecticut |
| 6502 | NEW HAVEN | Connecticut |
| 6503 | N HAVEN | Connecticut |
| 6503 | NEW HAVEN | Connecticut |
| 6504 | N HAVEN | Connecticut |
| 6504 | NEW HAVEN | Connecticut |
| 6505 | N HAVEN | Connecticut |
| 6505 | NEW HAVEN | Connecticut |
| 6506 | N HAVEN | Connecticut |
| 6506 | NEW HAVEN | Connecticut |
| 6507 | N HAVEN | Connecticut |
| 6507 | NEW HAVEN | Connecticut |
| 6508 | N HAVEN | Connecticut |
| 6508 | NEW HAVEN | Connecticut |
| 6509 | N HAVEN | Connecticut |
| 6509 | NEW HAVEN | Connecticut |
| 6510 | N HAVEN | Connecticut |
| 6510 | NEW HAVEN | Connecticut |
| 6511 | HAMDEN | Connecticut |
| 6511 | NEW HAVEN | Connecticut |
| 6512 | EAST HAVEN | Connecticut |
| 6512 | N HAVEN | Connecticut |
| 6512 | NEW HAVEN | Connecticut |
| 6513 | E HAVEN | Connecticut |
| 6513 | EAST HAVEN | Connecticut |
| 6513 | FAIR HAVEN | Connecticut |
| 6513 | N HAVEN | Connecticut |
| 6513 | NEW HAVEN | Connecticut |
| 6514 | HAMDEN | Connecticut |
| 6514 | N HAVEN | Connecticut |
| 6514 | NEW HAVEN | Connecticut |
| 6515 | N HAVEN | Connecticut |
| 6515 | NEW HAVEN | Connecticut |
| 6515 | WESTVILLE | Connecticut |
| 6516 | N HAVEN | Connecticut |
| 6516 | W HAVEN | Connecticut |
| 6516 | WEST HAVEN | Connecticut |
| 6517 | HAMDEN | Connecticut |
| 6517 | NEW HAVEN | Connecticut |
| 6517 | WHITNEYVILLE | Connecticut |
| 6518 | CENTERVILLE MOUNT CARMEL | Connecticut |
| 6518 | HAMDEN | Connecticut |
| 6518 | MOUNT CARMEL | Connecticut |
| 6518 | N HAVEN | Connecticut |
| 6518 | NEW HAVEN | Connecticut |
| 6519 | N HAVEN | Connecticut |
| 6519 | NEW HAVEN | Connecticut |
| 6520 | N HAVEN | Connecticut |
| 6520 | NEW HAVEN | Connecticut |
| 6521 | N HAVEN | Connecticut |
| 6521 | NEW HAVEN | Connecticut |
| 6524 | BETHANY | Connecticut |
| 6524 | NEW HAVEN | Connecticut |
| 6525 | N HAVEN | Connecticut |
| 6525 | NEW HAVEN | Connecticut |
| 6525 | WOODBRIDGE | Connecticut |
| 6530 | N HAVEN | Connecticut |
| 6530 | NEW HAVEN | Connecticut |
| 6531 | N HAVEN | Connecticut |
| 6531 | NEW HAVEN | Connecticut |
| 6532 | N HAVEN | Connecticut |
| 6532 | NEW HAVEN | Connecticut |
| 6533 | N HAVEN | Connecticut |
| 6533 | NEW HAVEN | Connecticut |
| 6534 | N HAVEN | Connecticut |
| 6534 | NEW HAVEN | Connecticut |
| 6535 | N HAVEN | Connecticut |
| 6535 | NEW HAVEN | Connecticut |
| 6536 | N HAVEN | Connecticut |
| 6536 | NEW HAVEN | Connecticut |
| 6537 | ADVERTISING DISTR CO | Connecticut |
| 6537 | N HAVEN | Connecticut |
| 6537 | NEW HAVEN | Connecticut |
| 6538 | ADVERTISING DISTR CO | Connecticut |
| 6538 | N HAVEN | Connecticut |
| 6538 | NEW HAVEN | Connecticut |
| 6540 | CONN BANK & TRUST CO | Connecticut |
| 6540 | NEW HAVEN | Connecticut |
| 6601 | BRIDGEPORT | Connecticut |
| 6602 | BRIDGEPORT | Connecticut |
| 6604 | BRIDGEPORT | Connecticut |
| 6605 | BRIDGEPORT | Connecticut |
| 6606 | BRIDGEPORT | Connecticut |
| 6607 | BRIDGEPORT | Connecticut |
| 6608 | BRIDGEPORT | Connecticut |
| 6610 | BRIDGEPORT | Connecticut |
| 6611 | TRUMBULL | Connecticut |
| 6612 | EASTON | Connecticut |
| 6614 | STRATFORD | Connecticut |
| 6615 | STRATFORD | Connecticut |
| 6673 | BRIDGEPORT | Connecticut |
| 6673 | PROMOTION MARKETING SER INC | Connecticut |
| 6699 | BRIDGEPORT | Connecticut |
| 6699 | CONTROLLED DISTRIBUTION | Connecticut |
| 6702 | WATERBURY | Connecticut |
| 6702 | WTBY | Connecticut |
| 6704 | PLAZA | Connecticut |
| 6704 | WATERBURY | Connecticut |
| 6704 | WTBY | Connecticut |
| 6705 | EAST END | Connecticut |
| 6705 | WATERBURY | Connecticut |
| 6705 | WOLCOTT | Connecticut |
| 6705 | WTBY | Connecticut |
| 6706 | WATERBURY | Connecticut |
| 6706 | WTBY | Connecticut |
| 6708 | WATERBURY | Connecticut |
| 6708 | WTBY | Connecticut |
| 6710 | WATERBURY | Connecticut |
| 6710 | WTBY | Connecticut |
| 6712 | PROSPECT | Connecticut |
| 6712 | WATERBURY | Connecticut |
| 6716 | WATERBURY | Connecticut |
| 6716 | WOLCOTT | Connecticut |
| 6762 | MIDDLEBURY | Connecticut |
| 6770 | NAUGATUCK | Connecticut |
| 6770 | UNION CITY | Connecticut |
| 6784 | SHERMAN | Connecticut |
| 6798 | WOODBURY | Connecticut |
| 6801 | BETHEL | Connecticut |
| 6804 | BROOKFIELD | Connecticut |
| 6804 | BROOKFIELD CENTER | Connecticut |
| 6804 | BROOKFLD CTR | Connecticut |
| 6807 | COS COB | Connecticut |
| 6810 | DANBURY | Connecticut |
| 6811 | DANBURY | Connecticut |
| 6812 | NEW FAIRFIELD | Connecticut |
| 6813 | DANBURY | Connecticut |
| 6814 | Danbury | Connecticut |
| 6814 | Shared Zip For Brm | Connecticut |
| 6816 | Danbury | Connecticut |
| 6816 | Grolier Entrprz Inc | Connecticut |
| 6817 | Danbury | Connecticut |
| 6817 | Union Carbide Corp | Connecticut |
| 6820 | DARIEN | Connecticut |
| 6820 | NOROTON | Connecticut |
| 6820 | NOROTON HEIGHTS | Connecticut |
| 6820 | TOKENEKE | Connecticut |
| 6824 | FAIRFIELD | Connecticut |
| 6825 | FAIRFIELD | Connecticut |
| 6828 | FAIRFIELD | Connecticut |
| 6828 | GENERAL ELECTRIC | Connecticut |
| 6829 | GEORGETOWN | Connecticut |
| 6830 | BELLE HAVEN | Connecticut |
| 6830 | GREENWICH | Connecticut |
| 6831 | GLENVILLE | Connecticut |
| 6831 | GREENWICH | Connecticut |
| 6836 | GREENWICH | Connecticut |
| 6838 | GREENS FARMS | Connecticut |
| 6840 | NEW CANAAN | Connecticut |
| 6850 | NORWALK | Connecticut |
| 6851 | NORWALK | Connecticut |
| 6852 | NORWALK | Connecticut |
| 6853 | NORWALK | Connecticut |
| 6853 | ROWAYTON | Connecticut |
| 6854 | NORWALK | Connecticut |
| 6854 | SOUTH NORWALK | Connecticut |
| 6855 | EAST NORWALK | Connecticut |
| 6855 | NORWALK | Connecticut |
| 6856 | NORWALK | Connecticut |
| 6857 | MBI INC | Connecticut |
| 6857 | NORWALK | Connecticut |
| 6858 | NORWALK | Connecticut |
| 6858 | SETAN INDUSTRIES | Connecticut |
| 6860 | NORWALK | Connecticut |
| 6860 | SHARED ZIP FOR BRM | Connecticut |
| 6870 | OLD GREENWICH | Connecticut |
| 6875 | REDDING CENTER | Connecticut |
| 6875 | REDDING CTR | Connecticut |
| 6876 | REDDING RIDGE | Connecticut |
| 6877 | RIDGEFIELD | Connecticut |
| 6878 | RIVERSIDE | Connecticut |
| 6879 | PROMOTION SYSTEMS INC | Connecticut |
| 6879 | RIDGEFIELD | Connecticut |
| 6880 | SAUGATUCK | Connecticut |
| 6880 | WESTPORT | Connecticut |
| 6881 | WESTPORT | Connecticut |
| 6883 | WESTON | Connecticut |
| 6888 | PROMOTIONAL DEV INC | Connecticut |
| 6888 | WESTPORT | Connecticut |
| 6889 | WEBSTERS UNIFIED | Connecticut |
| 6889 | WESTPORT | Connecticut |
| 6890 | SOUTHPORT | Connecticut |
| 6896 | REDDING | Connecticut |
| 6896 | WEST REDDING | Connecticut |
| 6897 | WILTON | Connecticut |
| 6901 | STAMFORD | Connecticut |
| 6902 | STAMFORD | Connecticut |
| 6903 | STAMFORD | Connecticut |
| 6904 | STAMFORD | Connecticut |
| 6905 | RIDGEWAY | Connecticut |
| 6905 | STAMFORD | Connecticut |
| 6906 | GLENBROOK | Connecticut |
| 6906 | STAMFORD | Connecticut |
| 6907 | SPRINGDALE | Connecticut |
| 6907 | STAMFORD | Connecticut |
| 6910 | STAMFORD | Connecticut |
| 6911 | STAMFORD | Connecticut |
| 6912 | STAMFORD | Connecticut |
| 6913 | SHARED ZIP FOR BRM | Connecticut |
| 6913 | STAMFORD | Connecticut |
| 6914 | SHARED ZIP FOR BRM | Connecticut |
| 6914 | STAMFORD | Connecticut |
| 6926 | PITNEY BOWES INC | Connecticut |
| 6926 | STAMFORD | Connecticut |
| 6927 | GECC | Connecticut |
| 6927 | STAMFORD | Connecticut |