Area Code 203
Area code 203 is in Connecticut, USA , spanning 3 counties and serving 67 cities, including Bridgeport, New Haven or Stamford; it currently uses 778 prefixes, assigned from 203-200-XXXX through 203-999-XXXX.
In service since January 01, 1947, area code 203 is the parent Numbering Plan Area in overlay complex 203/475.
The current local time is .
For exact NPA boundaries see official 203 area code map
Phone number lookup
More Connecticut area codes:
Locate any 203-NXX prefix:
| NPANXX | Area Served1 | Date1 |
|---|---|---|
| 203-200 | New Haven | 8/14/2008 |
| 203-201 | New Haven | N/A |
| 203-202 | Darien | N/A |
| 203-203 | Greenwich | 09/18/2024 |
| 203-204 | Guilford | N/A |
| 203-205 | Danbury | N/A |
| 203-206 | Waterbury | N/A |
| 203-207 | Danbury | N/A |
| 203-208 | Branford | N/A |
| 203-209 | Bridgeport | N/A |
| 203-210 | Wilton | N/A |
| 203-212 | Bridgeport | 10/23/2008 |
| 203-213 | Meriden | N/A |
| 203-214 | New Haven | N/A |
| 203-215 | New Haven | N/A |
| 203-216 | Westport | N/A |
| 203-217 | Waterbury | N/A |
| 203-218 | Bridgeport | N/A |
| 203-219 | Stamford | N/A |
| 203-220 | Trumbull | N/A |
| 203-221 | Westport | N/A |
| 203-222 | Westport | N/A |
| 203-223 | Stamford | N/A |
| 203-224 | Bridgeport | N/A |
| 203-225 | Huntington | N/A |
| 203-226 | Westport | N/A |
| 203-227 | Westport | N/A |
| 203-228 | Waterbury | 10/4/2002 |
| 203-229 | Norwalk | N/A |
| 203-230 | New Haven | N/A |
| 203-231 | Ansonia/ Derby | N/A |
| 203-232 | Waterbury | N/A |
| 203-233 | Waterbury | N/A |
| 203-234 | New Haven | N/A |
| 203-235 | Meriden | N/A |
| 203-236 | Waterbury | N/A |
| 203-237 | Meriden | N/A |
| 203-238 | Meriden | N/A |
| 203-239 | New Haven | N/A |
| 203-240 | Danbury | N/A |
| 203-241 | Danbury | N/A |
| 203-242 | Huntington | N/A |
| 203-243 | Bridgeport | N/A |
| 203-244 | Ridgefield | 3/28/2003 |
| 203-245 | Madison | N/A |
| 203-246 | Norwalk | N/A |
| 203-247 | Norwalk | N/A |
| 203-248 | New Haven | N/A |
| 203-249 | Stamford | N/A |
| 203-250 | Cheshire | N/A |
| 203-251 | Stamford | N/A |
| 203-252 | Stamford | N/A |
| 203-253 | Stamford | N/A |
| 203-254 | Fairfield | N/A |
| 203-255 | Fairfield | N/A |
| 203-256 | Fairfield | N/A |
| 203-257 | Bridgeport | N/A |
| 203-258 | Bridgeport | N/A |
| 203-259 | Fairfield | N/A |
| 203-260 | Bridgeport | N/A |
| 203-261 | Trumbull | N/A |
| 203-262 | Woodbury | N/A |
| 203-263 | Woodbury | N/A |
| 203-264 | Woodbury | N/A |
| 203-265 | Wallingford | N/A |
| 203-266 | Woodbury | N/A |
| 203-267 | Woodbury | N/A |
| 203-268 | Trumbull | N/A |
| 203-269 | Wallingford | N/A |
| 203-270 | Newtown | N/A |
| 203-271 | Cheshire | N/A |
| 203-272 | Cheshire | N/A |
| 203-273 | Stamford | 10/22/2002 |
| 203-274 | Stamford | N/A |
| 203-275 | Bridgeport | N/A |
| 203-276 | Stamford | 3/28/2003 |
| 203-277 | Old Greenwich | 4/16/2003 |
| 203-278 | Ansonia/ Derby | 5/1/2001 |
| 203-279 | Bridgeport | N/A |
| 203-280 | Darien | 3/24/2004 |
| 203-281 | New Haven | N/A |
| 203-282 | Stamford | N/A |
| 203-283 | Milford | N/A |
| 203-284 | Wallingford | N/A |
| 203-285 | New Haven | N/A |
| 203-286 | Norwalk | N/A |
| 203-287 | New Haven | N/A |
| 203-288 | New Haven | N/A |
| 203-289 | Danbury | N/A |
| 203-290 | Bridgeport | 11/14/2013 |
| 203-291 | Westport | N/A |
| 203-292 | Fairfield | N/A |
| 203-293 | Westport | N/A |
| 203-294 | Wallingford | N/A |
| 203-295 | Norwalk | N/A |
| 203-296 | Bridgeport | N/A |
| 203-297 | Danbury | N/A |
| 203-298 | New Haven | N/A |
| 203-299 | Norwalk | N/A |
| NPANXX | Area Served1 | Date1 |
|---|---|---|
| 203-300 | Danbury | 10/25/2001 |
| 203-301 | Milford | N/A |
| 203-302 | Greenwich | N/A |
| 203-303 | Wallingford | N/A |
| 203-304 | Newtown | N/A |
| 203-305 | Ansonia/ Derby | N/A |
| 203-306 | Milford | N/A |
| 203-307 | Fairfield | 1/31/2005 |
| 203-308 | Ansonia/ Derby | 10/22/2008 |
| 203-309 | Darien | 9/11/2007 |
| 203-310 | New Canaan | 4/16/2003 |
| 203-312 | Danbury | N/A |
| 203-313 | Danbury | N/A |
| 203-314 | New Haven | N/A |
| 203-315 | Branford | N/A |
| 203-316 | Stamford | N/A |
| 203-317 | Meriden | N/A |
| 203-318 | Madison | N/A |
| 203-319 | Fairfield | N/A |
| 203-320 | Darien | 4/16/2003 |
| 203-321 | Stamford | N/A |
| 203-322 | Stamford | N/A |
| 203-323 | Stamford | N/A |
| 203-324 | Stamford | N/A |
| 203-325 | Stamford | N/A |
| 203-326 | Stamford | N/A |
| 203-327 | Stamford | N/A |
| 203-328 | Stamford | N/A |
| 203-329 | Stamford | N/A |
| 203-330 | Bridgeport | N/A |
| 203-331 | Bridgeport | N/A |
| 203-332 | Bridgeport | N/A |
| 203-333 | Bridgeport | N/A |
| 203-334 | Bridgeport | N/A |
| 203-335 | Bridgeport | N/A |
| 203-336 | Bridgeport | N/A |
| 203-337 | Bridgeport | N/A |
| 203-338 | Bridgeport | N/A |
| 203-339 | Bridgeport | N/A |
| 203-340 | Greenwich | 8/19/2003 |
| 203-341 | Westport | N/A |
| 203-342 | Bridgeport | N/A |
| 203-343 | Ansonia/ Derby | 1/18/2012 |
| 203-344 | Old Greenwich | N/A |
| 203-345 | Bridgeport | N/A |
| 203-346 | Waterbury | N/A |
| 203-347 | Byram | 3/11/2004 |
| 203-348 | Stamford | N/A |
| 203-349 | Westport | N/A |
| 203-350 | Madison | N/A |
| 203-351 | Stamford | N/A |
| 203-352 | Stamford | N/A |
| 203-353 | Stamford | N/A |
| 203-354 | Norwalk | N/A |
| 203-355 | Stamford | N/A |
| 203-356 | Stamford | N/A |
| 203-357 | Stamford | N/A |
| 203-358 | Stamford | N/A |
| 203-359 | Stamford | N/A |
| 203-360 | Bridgeport | 12/10/2008 |
| 203-361 | New Haven | 12/16/2010 |
| 203-362 | Bridgeport | N/A |
| 203-363 | Stamford | N/A |
| 203-364 | Newtown | N/A |
| 203-365 | Bridgeport | N/A |
| 203-366 | Bridgeport | N/A |
| 203-367 | Bridgeport | N/A |
| 203-368 | Bridgeport | N/A |
| 203-369 | Old Greenwich | 10/7/2003 |
| 203-370 | New Haven | N/A |
| 203-371 | Bridgeport | N/A |
| 203-372 | Bridgeport | N/A |
| 203-373 | Bridgeport | N/A |
| 203-374 | Bridgeport | N/A |
| 203-375 | Bridgeport | N/A |
| 203-376 | New Haven | N/A |
| 203-377 | Bridgeport | N/A |
| 203-378 | Bridgeport | N/A |
| 203-379 | Meriden | N/A |
| 203-380 | Bridgeport | N/A |
| 203-381 | Bridgeport | N/A |
| 203-382 | Bridgeport | N/A |
| 203-383 | Bridgeport | N/A |
| 203-384 | Bridgeport | N/A |
| 203-385 | Bridgeport | N/A |
| 203-386 | Bridgeport | N/A |
| 203-387 | New Haven | N/A |
| 203-388 | Stamford | N/A |
| 203-389 | New Haven | N/A |
| 203-390 | New Haven | 11/10/2015 |
| 203-391 | Stamford | N/A |
| 203-392 | New Haven | N/A |
| 203-393 | New Haven | N/A |
| 203-394 | Bridgeport | N/A |
| 203-395 | Bridgeport | N/A |
| 203-396 | Bridgeport | N/A |
| 203-397 | New Haven | N/A |
| 203-398 | Norwalk | N/A |
| 203-399 | Stamford | N/A |
| NPANXX | Area Served1 | Date1 |
|---|---|---|
| 203-400 | Trumbull | 2/19/2002 |
| 203-401 | New Haven | N/A |
| 203-402 | Huntington | N/A |
| 203-403 | Ridgefield | N/A |
| 203-404 | New Haven | N/A |
| 203-405 | Woodbury | 4/4/2001 |
| 203-406 | Stamford | N/A |
| 203-407 | New Haven | N/A |
| 203-408 | Redding | N/A |
| 203-409 | Old Greenwich | N/A |
| 203-410 | New Haven | N/A |
| 203-412 | New Haven | N/A |
| 203-413 | Greenwich | N/A |
| 203-414 | Bridgeport | N/A |
| 203-415 | New Haven | 4/12/2001 |
| 203-416 | Bridgeport | N/A |
| 203-417 | Danbury | N/A |
| 203-418 | Fairfield | N/A |
| 203-419 | Waterbury | N/A |
| 203-420 | Meriden | N/A |
| 203-421 | Madison | N/A |
| 203-422 | Greenwich | N/A |
| 203-423 | Wilton | N/A |
| 203-424 | Darien | 6/29/2007 |
| 203-425 | Stamford | N/A |
| 203-426 | Newtown | N/A |
| 203-427 | Meriden | N/A |
| 203-428 | Stamford | N/A |
| 203-429 | Westport | N/A |
| 203-430 | New Haven | N/A |
| 203-431 | Ridgefield | N/A |
| 203-432 | New Haven | N/A |
| 203-433 | Branford | N/A |
| 203-434 | Norwalk | N/A |
| 203-435 | New Haven | N/A |
| 203-436 | New Haven | N/A |
| 203-437 | Waterbury | N/A |
| 203-438 | Ridgefield | N/A |
| 203-439 | Cheshire | N/A |
| 203-440 | Meriden | N/A |
| 203-441 | Wolcott | N/A |
| 203-442 | New Canaan | N/A |
| 203-443 | Meriden | N/A |
| 203-444 | New Haven | N/A |
| 203-445 | Trumbull | N/A |
| 203-446 | Ansonia/ Derby | N/A |
| 203-447 | Huntington | N/A |
| 203-448 | Danbury | N/A |
| 203-449 | Bridgeport | N/A |
| 203-450 | Bridgeport | 5/12/2008 |
| 203-451 | Westport | N/A |
| 203-452 | Trumbull | N/A |
| 203-453 | Guilford | N/A |
| 203-454 | Westport | N/A |
| 203-455 | Bridgeport | N/A |
| 203-456 | Danbury | 12/6/2011 |
| 203-457 | Guilford | N/A |
| 203-458 | Guilford | N/A |
| 203-459 | Trumbull | N/A |
| 203-460 | Danbury | N/A |
| 203-461 | Stamford | N/A |
| 203-462 | Stamford | N/A |
| 203-463 | Seymour | N/A |
| 203-464 | New Haven | N/A |
| 203-465 | Waterbury | N/A |
| 203-466 | New Haven | N/A |
| 203-467 | New Haven | N/A |
| 203-468 | New Haven | N/A |
| 203-469 | New Haven | N/A |
| 203-470 | Danbury | N/A |
| 203-477 | New Haven | N/A |
| 203-479 | New Haven | N/A |
| 203-480 | Fairfield | N/A |
| 203-481 | Branford | N/A |
| 203-482 | Danbury | 3/23/2001 |
| 203-483 | Branford | N/A |
| 203-484 | Branford | N/A |
| 203-485 | Greenwich | N/A |
| 203-486 | Woodbury | N/A |
| 203-487 | Stamford | 1/3/2001 |
| 203-488 | Branford | N/A |
| 203-489 | Greenwich | 5/25/2011 |
| 203-490 | Naugatuck | N/A |
| 203-491 | Newtown | 2/12/2010 |
| 203-492 | New Haven | N/A |
| 203-493 | Georgetown | N/A |
| 203-494 | New Haven | N/A |
| 203-495 | New Haven | N/A |
| 203-496 | Greenwich | N/A |
| 203-497 | New Haven | N/A |
| 203-498 | New Haven | N/A |
| 203-499 | New Haven | N/A |
| NPANXX | Area Served1 | Date1 |
|---|---|---|
| 203-500 | New Haven | 10/25/2001 |
| 203-501 | Danbury | 7/9/2010 |
| 203-502 | Bridgeport | N/A |
| 203-503 | New Haven | N/A |
| 203-504 | Stamford | 2/12/2004 |
| 203-505 | Norwalk | N/A |
| 203-506 | New Haven | N/A |
| 203-507 | New Haven | N/A |
| 203-508 | New Haven | 2/3/2005 |
| 203-509 | Waterbury | N/A |
| 203-510 | Waterbury | N/A |
| 203-512 | Danbury | N/A |
| 203-513 | Huntington | N/A |
| 203-514 | Meriden | N/A |
| 203-515 | Norwalk | N/A |
| 203-516 | Ansonia/ Derby | N/A |
| 203-517 | Stamford | N/A |
| 203-518 | Waterbury | 7/2/2001 |
| 203-519 | Waterbury | 2/9/2011 |
| 203-520 | Bridgeport | 5/30/2002 |
| 203-521 | Bridgeport | N/A |
| 203-522 | Bridgeport | N/A |
| 203-523 | Norwalk | N/A |
| 203-524 | Stamford | N/A |
| 203-525 | Waterbury | N/A |
| 203-526 | Bridgeport | N/A |
| 203-527 | Waterbury | N/A |
| 203-528 | Waterbury | N/A |
| 203-529 | Wilton | N/A |
| 203-530 | New Haven | N/A |
| 203-531 | Byram | N/A |
| 203-532 | Byram | N/A |
| 203-533 | Guilford | N/A |
| 203-534 | Bridgeport | N/A |
| 203-535 | New Haven | N/A |
| 203-536 | Stamford | N/A |
| 203-537 | Meriden | N/A |
| 203-538 | Huntington | N/A |
| 203-539 | Stamford | N/A |
| 203-540 | Bridgeport | 1/31/2005 |
| 203-541 | Stamford | N/A |
| 203-542 | Greenwich | N/A |
| 203-543 | Bridgeport | N/A |
| 203-544 | Georgetown | N/A |
| 203-545 | Bridgeport | N/A |
| 203-546 | Danbury | N/A |
| 203-547 | Stamford | N/A |
| 203-548 | Stamford | 5/30/2002 |
| 203-549 | Bridgeport | N/A |
| 203-550 | Stamford | N/A |
| 203-551 | Bridgeport | N/A |
| 203-552 | Byram | N/A |
| 203-553 | New Haven | N/A |
| 203-554 | Stamford | N/A |
| 203-556 | Bridgeport | N/A |
| 203-557 | Westport | N/A |
| 203-558 | Waterbury | N/A |
| 203-559 | Darien | N/A |
| 203-560 | Waterbury | N/A |
| 203-561 | Stamford | N/A |
| 203-562 | New Haven | N/A |
| 203-563 | Wilton | N/A |
| 203-564 | Stamford | N/A |
| 203-565 | Waterbury | N/A |
| 203-566 | Stamford | 2/4/2003 |
| 203-567 | Huntington | N/A |
| 203-568 | Waterbury | N/A |
| 203-569 | Stamford | N/A |
| 203-570 | Stamford | 3/26/2001 |
| 203-571 | Westport | N/A |
| 203-572 | Bridgeport | 7/13/2007 |
| 203-573 | Waterbury | N/A |
| 203-574 | Waterbury | N/A |
| 203-575 | Waterbury | N/A |
| 203-576 | Bridgeport | N/A |
| 203-577 | Waterbury | N/A |
| 203-578 | Waterbury | N/A |
| 203-579 | Bridgeport | N/A |
| 203-580 | Byram | 10/2/2012 |
| 203-581 | Bridgeport | N/A |
| 203-582 | New Haven | N/A |
| 203-583 | Bridgeport | N/A |
| 203-584 | New Haven | 7/9/2010 |
| 203-585 | Stamford | N/A |
| 203-586 | Woodbury | N/A |
| 203-587 | Georgetown | N/A |
| 203-588 | Stamford | N/A |
| 203-589 | New Haven | N/A |
| 203-590 | Trumbull | 3/18/2011 |
| 203-591 | Waterbury | N/A |
| 203-592 | Waterbury | N/A |
| 203-593 | Norwalk | N/A |
| 203-594 | New Canaan | N/A |
| 203-595 | Stamford | N/A |
| 203-596 | Waterbury | N/A |
| 203-597 | Waterbury | N/A |
| 203-598 | Waterbury | N/A |
| 203-599 | Meriden | N/A |
| NPANXX | Area Served1 | Date1 |
|---|---|---|
| 203-600 | Meriden | 10/3/2008 |
| 203-601 | Trumbull | N/A |
| 203-602 | Stamford | N/A |
| 203-603 | New Haven | N/A |
| 203-604 | Norwalk | 3/14/2001 |
| 203-605 | New Haven | N/A |
| 203-606 | New Haven | N/A |
| 203-607 | Stamford | 2/4/2003 |
| 203-608 | Meriden | N/A |
| 203-609 | Stamford | N/A |
| 203-610 | Bridgeport | N/A |
| 203-612 | Bridgeport | N/A |
| 203-613 | Norwalk | N/A |
| 203-614 | Stamford | N/A |
| 203-615 | Bridgeport | N/A |
| 203-616 | Danbury | N/A |
| 203-617 | Danbury | 9/5/2006 |
| 203-618 | Greenwich | N/A |
| 203-619 | New Haven | N/A |
| 203-620 | Darien | 7/19/2004 |
| 203-621 | Darien | N/A |
| 203-622 | Greenwich | N/A |
| 203-623 | New Haven | N/A |
| 203-624 | New Haven | N/A |
| 203-625 | Greenwich | N/A |
| 203-626 | Wallingford | N/A |
| 203-627 | New Haven | N/A |
| 203-628 | Danbury | N/A |
| 203-629 | Greenwich | N/A |
| 203-630 | Meriden | N/A |
| 203-631 | Meriden | N/A |
| 203-632 | Naugatuck | N/A |
| 203-633 | Wolcott | N/A |
| 203-634 | Meriden | N/A |
| 203-635 | Westport | N/A |
| 203-636 | Darien | 9/14/2004 |
| 203-637 | Old Greenwich | N/A |
| 203-638 | Trumbull | N/A |
| 203-639 | Meriden | N/A |
| 203-640 | New Haven | N/A |
| 203-641 | New Haven | N/A |
| 203-642 | Norwalk | N/A |
| 203-643 | Branford | N/A |
| 203-644 | Norwalk | N/A |
| 203-645 | New Haven | N/A |
| 203-646 | Branford | N/A |
| 203-647 | Milford | N/A |
| 203-648 | Danbury | N/A |
| 203-649 | Cheshire | N/A |
| 203-650 | Bridgeport | 3/26/2001 |
| 203-651 | Cheshire | N/A |
| 203-652 | New Canaan | N/A |
| 203-653 | Stamford | N/A |
| 203-654 | New Haven | N/A |
| 203-655 | Darien | N/A |
| 203-656 | Darien | N/A |
| 203-657 | New Haven | N/A |
| 203-658 | Stamford | N/A |
| 203-659 | Fairfield | N/A |
| 203-660 | Byram | 1/3/2001 |
| 203-661 | Greenwich | N/A |
| 203-662 | Darien | N/A |
| 203-663 | Norwalk | N/A |
| 203-664 | Redding | N/A |
| 203-665 | Wilton | N/A |
| 203-666 | Bridgeport | 9/26/2013 |
| 203-667 | Stamford | N/A |
| 203-668 | New Haven | N/A |
| 203-669 | Darien | N/A |
| 203-670 | Fairfield | 12/6/2021 |
| 203-671 | New Haven | N/A |
| 203-672 | New Haven | N/A |
| 203-673 | Bridgeport | N/A |
| 203-674 | Stamford | N/A |
| 203-675 | New Haven | N/A |
| 203-676 | New Haven | N/A |
| 203-677 | Wallingford | N/A |
| 203-678 | Wallingford | N/A |
| 203-679 | Wallingford | N/A |
| 203-680 | New Haven | 10/31/2012 |
| 203-681 | Byram | N/A |
| 203-682 | Westport | N/A |
| 203-683 | Bridgeport | N/A |
| 203-684 | New Haven | 10/3/2008 |
| 203-685 | Bridgeport | 3/30/2001 |
| 203-686 | Meriden | N/A |
| 203-687 | New Haven | N/A |
| 203-688 | New Haven | N/A |
| 203-689 | Guilford | N/A |
| 203-690 | Bridgeport | 3/21/2008 |
| 203-691 | New Haven | N/A |
| 203-692 | Fairfield | N/A |
| 203-693 | Milford | 7/13/2010 |
| 203-694 | Meriden | N/A |
| 203-695 | Waterbury | N/A |
| 203-696 | Bridgeport | N/A |
| 203-697 | Wallingford | N/A |
| 203-698 | Old Greenwich | N/A |
| 203-699 | Cheshire | N/A |
| NPANXX | Area Served1 | Date1 |
|---|---|---|
| 203-701 | Milford | N/A |
| 203-702 | Danbury | N/A |
| 203-703 | Stamford | N/A |
| 203-704 | Wolcott | 7/17/2002 |
| 203-705 | Stamford | N/A |
| 203-706 | Waterbury | 2/12/2004 |
| 203-707 | Waterbury | 3/10/2011 |
| 203-708 | Stamford | N/A |
| 203-709 | Waterbury | N/A |
| 203-710 | New Haven | N/A |
| 203-712 | Huntington | N/A |
| 203-713 | Milford | N/A |
| 203-714 | Naugatuck | N/A |
| 203-715 | Meriden | N/A |
| 203-716 | New Canaan | N/A |
| 203-717 | Greenwich | 1/28/2011 |
| 203-718 | Cheshire | N/A |
| 203-719 | Stamford | N/A |
| 203-720 | Naugatuck | N/A |
| 203-721 | Waterbury | N/A |
| 203-722 | Norwalk | N/A |
| 203-723 | Naugatuck | N/A |
| 203-724 | Stamford | N/A |
| 203-725 | Waterbury | N/A |
| 203-726 | Bridgeport | 9/8/2010 |
| 203-727 | Bridgeport | 6/5/2001 |
| 203-728 | Stamford | 11/22/2006 |
| 203-729 | Naugatuck | N/A |
| 203-730 | Danbury | N/A |
| 203-731 | Danbury | N/A |
| 203-732 | Ansonia/ Derby | N/A |
| 203-733 | Danbury | N/A |
| 203-734 | Ansonia/ Derby | N/A |
| 203-735 | Ansonia/ Derby | N/A |
| 203-736 | Ansonia/ Derby | N/A |
| 203-737 | New Haven | N/A |
| 203-738 | Guilford | N/A |
| 203-739 | Danbury | N/A |
| 203-740 | Danbury | N/A |
| 203-741 | Wallingford | N/A |
| 203-742 | Greenwich | 4/10/2003 |
| 203-743 | Danbury | N/A |
| 203-744 | Danbury | N/A |
| 203-745 | New Haven | N/A |
| 203-746 | Danbury | N/A |
| 203-747 | New Haven | N/A |
| 203-748 | Danbury | N/A |
| 203-749 | Danbury | N/A |
| 203-750 | Norwalk | N/A |
| 203-751 | Ansonia/ Derby | N/A |
| 203-752 | New Haven | N/A |
| 203-753 | Waterbury | N/A |
| 203-754 | Waterbury | N/A |
| 203-755 | Waterbury | N/A |
| 203-756 | Waterbury | N/A |
| 203-757 | Waterbury | N/A |
| 203-758 | Waterbury | N/A |
| 203-759 | Waterbury | N/A |
| 203-760 | Bridgeport | 4/16/2012 |
| 203-761 | Wilton | N/A |
| 203-762 | Wilton | N/A |
| 203-763 | Fairfield | N/A |
| 203-764 | New Haven | N/A |
| 203-765 | New Haven | N/A |
| 203-766 | New Haven | N/A |
| 203-767 | Bridgeport | N/A |
| 203-768 | Waterbury | N/A |
| 203-769 | Greenwich | N/A |
| 203-770 | Danbury | N/A |
| 203-771 | New Haven | N/A |
| 203-772 | New Haven | N/A |
| 203-773 | New Haven | N/A |
| 203-774 | Wallingford | N/A |
| 203-775 | Danbury | N/A |
| 203-776 | New Haven | N/A |
| 203-777 | New Haven | N/A |
| 203-778 | Danbury | N/A |
| 203-779 | Madison | N/A |
| 203-780 | New Haven | 10/2/2012 |
| 203-781 | New Haven | N/A |
| 203-782 | New Haven | N/A |
| 203-783 | Milford | N/A |
| 203-784 | New Haven | N/A |
| 203-785 | New Haven | N/A |
| 203-786 | New Haven | N/A |
| 203-787 | New Haven | N/A |
| 203-788 | Danbury | N/A |
| 203-789 | New Haven | N/A |
| 203-790 | Danbury | N/A |
| 203-791 | Danbury | N/A |
| 203-792 | Danbury | N/A |
| 203-793 | Wallingford | 3/23/2001 |
| 203-794 | Danbury | N/A |
| 203-795 | New Haven | N/A |
| 203-796 | Danbury | N/A |
| 203-797 | Danbury | N/A |
| 203-798 | Danbury | N/A |
| 203-799 | New Haven | N/A |
| NPANXX | Area Served1 | Date1 |
|---|---|---|
| 203-800 | New Haven | 3/10/2011 |
| 203-801 | New Canaan | N/A |
| 203-802 | Waterbury | 10/3/2008 |
| 203-803 | Norwalk | N/A |
| 203-804 | New Haven | N/A |
| 203-805 | Waterbury | N/A |
| 203-806 | Cheshire | N/A |
| 203-807 | Norwalk | 1/30/2001 |
| 203-808 | Waterbury | 5/30/2002 |
| 203-809 | New Haven | 11/4/2002 |
| 203-810 | Norwalk | 7/27/2001 |
| 203-812 | New Haven | N/A |
| 203-813 | Byram | N/A |
| 203-814 | Bridgeport | N/A |
| 203-815 | New Haven | N/A |
| 203-816 | Trumbull | 3/14/2001 |
| 203-817 | Stamford | N/A |
| 203-818 | Norwalk | N/A |
| 203-819 | Waterbury | N/A |
| 203-820 | Norwalk | N/A |
| 203-821 | New Haven | N/A |
| 203-822 | Norwalk | N/A |
| 203-823 | New Haven | N/A |
| 203-824 | New Haven | N/A |
| 203-825 | Danbury | N/A |
| 203-826 | Danbury | N/A |
| 203-827 | Old Greenwich | 7/19/2004 |
| 203-828 | Seymour | N/A |
| 203-829 | Norwalk | N/A |
| 203-830 | Danbury | N/A |
| 203-831 | Norwalk | N/A |
| 203-832 | Stamford | 4/6/2006 |
| 203-833 | New Haven | 7/29/2015 |
| 203-834 | Wilton | N/A |
| 203-835 | Norwalk | N/A |
| 203-836 | New Haven | 12/6/2011 |
| 203-837 | Danbury | N/A |
| 203-838 | Norwalk | N/A |
| 203-839 | Norwalk | N/A |
| 203-840 | Norwalk | N/A |
| 203-841 | Waterbury | N/A |
| 203-842 | Norwalk | N/A |
| 203-843 | New Haven | N/A |
| 203-844 | Fairfield | 8/16/2004 |
| 203-845 | Norwalk | N/A |
| 203-846 | Norwalk | N/A |
| 203-847 | Norwalk | N/A |
| 203-848 | New Haven | N/A |
| 203-849 | Norwalk | N/A |
| 203-850 | New Haven | 10/3/2008 |
| 203-851 | Norwalk | N/A |
| 203-852 | Norwalk | N/A |
| 203-853 | Norwalk | N/A |
| 203-854 | Norwalk | N/A |
| 203-855 | Norwalk | N/A |
| 203-856 | Norwalk | N/A |
| 203-857 | Norwalk | N/A |
| 203-858 | Norwalk | N/A |
| 203-859 | New Haven | N/A |
| 203-861 | Greenwich | N/A |
| 203-862 | Greenwich | N/A |
| 203-863 | Greenwich | N/A |
| 203-864 | Bridgeport | 3/7/2011 |
| 203-865 | New Haven | N/A |
| 203-866 | Norwalk | N/A |
| 203-867 | New Haven | N/A |
| 203-868 | New Haven | N/A |
| 203-869 | Greenwich | N/A |
| 203-870 | Bridgeport | N/A |
| 203-871 | Branford | N/A |
| 203-872 | Cheshire | N/A |
| 203-873 | Bridgeport | 2/7/2007 |
| 203-874 | Milford | N/A |
| 203-875 | Darien | N/A |
| 203-876 | Milford | N/A |
| 203-877 | Milford | N/A |
| 203-878 | Milford | N/A |
| 203-879 | Wolcott | N/A |
| 203-880 | Trumbull | N/A |
| 203-881 | Seymour | N/A |
| 203-882 | Milford | N/A |
| 203-883 | Stamford | N/A |
| 203-884 | Guilford | N/A |
| 203-885 | Danbury | 10/30/2006 |
| 203-886 | Meriden | N/A |
| 203-887 | New Haven | N/A |
| 203-888 | Seymour | N/A |
| 203-889 | New Haven | N/A |
| 203-890 | Stamford | 7/27/2001 |
| 203-891 | New Haven | N/A |
| 203-892 | Ansonia/ Derby | 11/8/2010 |
| 203-893 | Ansonia/ Derby | 6/29/2007 |
| 203-894 | Ridgefield | N/A |
| 203-895 | Trumbull | N/A |
| 203-896 | Madison | N/A |
| 203-897 | Stamford | 8/20/2008 |
| 203-898 | Darien | 1/31/2005 |
| 203-899 | Norwalk | N/A |
| NPANXX | Area Served1 | Date1 |
|---|---|---|
| 203-900 | Greenwich | 2/24/2012 |
| 203-901 | New Haven | N/A |
| 203-902 | New Haven | N/A |
| 203-903 | New Haven | N/A |
| 203-904 | Norwalk | N/A |
| 203-905 | Stamford | N/A |
| 203-906 | Ansonia/ Derby | 4/23/2002 |
| 203-907 | New Haven | N/A |
| 203-908 | Bridgeport | 4/5/2006 |
| 203-909 | New Haven | 5/13/2008 |
| 203-910 | Waterbury | N/A |
| 203-912 | Stamford | N/A |
| 203-913 | Bridgeport | N/A |
| 203-914 | Stamford | 2/24/2012 |
| 203-915 | New Haven | N/A |
| 203-916 | Bridgeport | 1/30/2001 |
| 203-917 | Danbury | 10/22/2008 |
| 203-918 | Stamford | N/A |
| 203-919 | Norwalk | N/A |
| 203-920 | New Canaan | 2/20/2004 |
| 203-921 | Stamford | N/A |
| 203-922 | Huntington | N/A |
| 203-923 | Bridgeport | N/A |
| 203-924 | Huntington | N/A |
| 203-925 | Huntington | N/A |
| 203-926 | Huntington | N/A |
| 203-927 | New Haven | N/A |
| 203-928 | New Haven | N/A |
| 203-929 | Huntington | N/A |
| 203-930 | Greenwich | 3/14/2001 |
| 203-931 | New Haven | N/A |
| 203-932 | New Haven | N/A |
| 203-933 | New Haven | N/A |
| 203-934 | New Haven | N/A |
| 203-935 | Meriden | N/A |
| 203-936 | New Haven | 9/12/2008 |
| 203-937 | New Haven | N/A |
| 203-938 | Redding | N/A |
| 203-939 | Norwalk | 6/25/2008 |
| 203-940 | Stamford | N/A |
| 203-941 | Seymour | 9/21/2010 |
| 203-942 | Danbury | N/A |
| 203-943 | Norwalk | N/A |
| 203-944 | Huntington | N/A |
| 203-945 | Norwalk | N/A |
| 203-946 | New Haven | N/A |
| 203-947 | Danbury | N/A |
| 203-948 | Danbury | N/A |
| 203-949 | Wallingford | N/A |
| 203-951 | Milford | N/A |
| 203-952 | Norwalk | N/A |
| 203-953 | Bridgeport | 7/27/2001 |
| 203-954 | Ansonia/ Derby | N/A |
| 203-955 | Fairfield | 2/20/2004 |
| 203-956 | Norwalk | 1/30/2001 |
| 203-957 | Norwalk | 5/25/2011 |
| 203-960 | Stamford | 9/15/2008 |
| 203-961 | Stamford | N/A |
| 203-962 | Stamford | N/A |
| 203-963 | Norwalk | N/A |
| 203-964 | Stamford | N/A |
| 203-965 | Stamford | N/A |
| 203-966 | New Canaan | N/A |
| 203-967 | Stamford | N/A |
| 203-968 | Stamford | N/A |
| 203-969 | Stamford | N/A |
| 203-970 | Norwalk | 4/4/2011 |
| 203-971 | Greenwich | N/A |
| 203-972 | New Canaan | N/A |
| 203-973 | Stamford | N/A |
| 203-974 | New Haven | N/A |
| 203-975 | Stamford | N/A |
| 203-977 | Stamford | N/A |
| 203-978 | Stamford | N/A |
| 203-979 | Stamford | N/A |
| 203-980 | New Haven | 8/20/2002 |
| 203-981 | Norwalk | N/A |
| 203-982 | Waterbury | N/A |
| 203-983 | Greenwich | N/A |
| 203-984 | Norwalk | N/A |
| 203-985 | New Haven | N/A |
| 203-986 | Old Greenwich | 2/20/2004 |
| 203-987 | Greenwich | 3/30/2001 |
| 203-988 | New Haven | N/A |
| 203-989 | Stamford | N/A |
| 203-990 | Old Greenwich | 1/31/2005 |
| 203-991 | Norwalk | N/A |
| 203-992 | Greenwich | 5/12/2006 |
| 203-993 | Bridgeport | 7/20/2006 |
| 203-994 | Danbury | 12/14/2001 |
| 203-995 | Bridgeport | 10/8/2008 |
| 203-996 | New Haven | 12/14/2001 |
| 203-997 | Ansonia/ Derby | 5/18/2011 |
| 203-998 | Stamford | 10/15/2004 |
| 203-999 | New Haven | 3/9/2011 |
- For 'Area served' we list the rate center. In the North American Numbering Plan a rate center is a geographic area used to determine local calling boundaries for billing purposes. Its name is generally a locality, often not the only one served by an NPA-NXX combination.
- Assignment date. N/A - mostly central office codes assigned before 2001.
- NXX prefixes last updated: June 3, 2025
Cities in area code 203
| City1 | County | Time Zone1 |
|---|---|---|
| Ansonia | New Haven | E |
| Beacon Falls | New Haven | E |
| Bethany | New Haven | E |
| Bethel | Fairfield | E |
| Bethlehem | Litchfield | E |
| Botsford | Fairfield | E |
| Branford | New Haven | E |
| Bridgeport | Fairfield | E |
| Brookfield | Fairfield | E |
| Cheshire | New Haven | E |
| Cos Cob | Fairfield | E |
| Danbury | Fairfield | E |
| Darien | Fairfield | E |
| Derby | New Haven | E |
| East Haven | New Haven | E |
| Easton | Fairfield | E |
| Fairfield | Fairfield | E |
| Georgetown | Fairfield | E |
| Greens Farms | Fairfield | E |
| Greenwich | Fairfield | E |
| Guilford | New Haven | E |
| Hamden | New Haven | E |
| Hawleyville | Fairfield | E |
| Madison | New Haven | E |
| Meriden | New Haven | E |
| Middlebury | New Haven | E |
| Milford | New Haven | E |
| Monroe | Fairfield | E |
| Naugatuck | New Haven | E |
| New Canaan | Fairfield | E |
| New Fairfield | Fairfield | E |
| New Haven | New Haven | E |
| Newtown | Fairfield | E |
| North Branford | New Haven | E |
| North Haven | New Haven | E |
| Northford | New Haven | E |
| Norwalk | Fairfield | E |
| Old Greenwich | Fairfield | E |
| Orange | New Haven | E |
| Oxford | New Haven | E |
| Prospect | New Haven | E |
| Redding | Fairfield | E |
| Redding Center | Fairfield | E |
| Redding Ridge | Fairfield | E |
| Ridgefield | Fairfield | E |
| Riverside | Fairfield | E |
| Roxbury | Litchfield | E |
| Sandy Hook | Fairfield | E |
| Seymour | New Haven | E |
| Shelton | Fairfield | E |
| Sherman | Fairfield | E |
| South Britain | New Haven | E |
| Southbury | New Haven | E |
| Southport | Fairfield | E |
| Stamford | Fairfield | E |
| Stevenson | Fairfield | E |
| Stratford | Fairfield | E |
| Trumbull | Fairfield | E |
| Wallingford | New Haven | E |
| Waterbury | New Haven | E |
| West Haven | New Haven | E |
| Weston | Fairfield | E |
| Westport | Fairfield | E |
| Wilton | Fairfield | E |
| Wolcott | New Haven | E |
| Woodbridge | New Haven | E |
| Woodbury | Litchfield | E |
- Listed above are most places served by USA area code 203. When multiple places in a US state share the same name we list the largest one only. Cities with population over 50,000 are displayed in bold text.
- E stands for Eastern Time (currently ).