Who Called Me from Area Code 303?
Quick answerA 303 call usually comes from Denver or nearby communities, but caller ID can be spoofed, so a local-looking number isn’t proof. If there’s no voicemail, let it go: legitimate callers leave messages.
- No voicemail? Let it go. Real callers leave messages.
- Recognize the pattern? Check the number in the prefix lookup.
- Getting repeats? ActiveArmor® blocks and labels them automatically.
- Same prefix calling again? Compare it against this month’s most-reported 303 prefixes, right on this page.
- Curious who issued a number? Every 303 prefix belongs to a carrier — the registry names it.
Been targeted?Report the call at reportfraud.ftc.gov — reports feed the complaint data that powers spam blocking, including the board on this page. AT&T customers already have ActiveArmor® screening built in.
Most-reported 303 prefixes this month
PrefixReported patternReport volume
(303) 704-XXXXRobocall-heavy
(303) 214-XXXXRobocall-heavy
(303) 712-XXXXRobocall-heavy
(303) 219-XXXXRobocall-heavy
(303) 339-XXXXRobocall-heavy
627 unwanted-call reports naming 303 numbers in FTC Do Not Call complaint data, July 2–17, 2026. Consumer-reported and unverified.
Block spam calls in the 303, included with AT&T wireless
AT&T ActiveArmor® is the network-level security that screens the calls this page is about:
- Fraud calls blocked automatically on the network
- Suspected spam labeled before you answer
- Caller ID & custom call blocking in the free app
- Reverse number lookup (available with ActiveArmor Advanced security. Fee required.)
- Identity monitoring & identity theft insurance (available with ActiveArmor Advanced security. Fee required.)
Included with AT&T wireless plans. Requires compatible device/service and download of the AT&T ActiveArmor® app. Other terms & restrictions apply. May not detect all threats and may block wanted calls. Some features require Advanced mobile security ($7/mo.). See terms.
See how ActiveArmor worksIncluded with the free 30-day AT&T Wireless℠ trialTry AT&T Wireless℠ free for 30 daysDownload the AT&T app, activate a trial eSIM in minutes, and run our network side by side with your current service. No credit card, keep your number.
- 100GB of data plus 25GB hotspot
- Unlimited talk & text in the U.S., Canada and Mexico
- Texting from the U.S. to 200+ countries & territories
- Access to the AT&T 5G network
Offer details
Service good for 30 days. Data: Limited to 100GB of data and 25GB of hotspot data. No additional data is available after limit is reached. Video is limited to SD quality. Talk & Text: Includes unlimited talk & text within the U.S. and unlimited text from the U.S. to over 230 countries. Limits: One trial per user. An unlocked, dual eSIM iPhone is required. You’ll receive a trial phone number that belongs to AT&T and is not available to be ported to another carrier or otherwise retained. Trial plan features and details may differ from or be unavailable in other AT&T plans. U.S. only. All terms subject to change at any time.
Is Area Code 303 a Scam?
No. 303 is a legitimate Denver area code.
It’s one of the original 1947 codes and serves Denver and surrounding communities. But legitimacy of the code says nothing about any single call. Scammers spoof local numbers constantly.
The code is realOriginal 1947 code for the Denver area with 784 assigned carrier prefixes.
Spoofing happens“Neighbor spoofing” fakes local numbers. No voicemail? Let it go.
Screening includedActiveArmor® labels and blocks suspected spam. Included with AT&T wireless plans.
Been targeted? Report it to the FTC at reportfraud.ftc.gov. Reports feed the complaint data that powers spam blocking.
Scam texts from area code 303 numbers
The most common area code 303 text scam is the “wrong number” opener: a friendly message that pretends to know you, then moves the chat to WhatsApp and eventually to an investment pitch. Scripts currently circulating:
- “U at home?” · “Are you busy tomorrow?” · “How are you doing?”
- Delivery-problem and job-offer texts that link out to a login page
Don’t reply. A response marks your number as live. Forward scam texts to 7726 (SPAM), and AT&T ActiveArmor® filters known senders automatically.
How number spoofing works in area code 303
Caller ID is easy to forge. Spoofing fakes the number a call displays. The real owner of that 303 number isn’t involved and usually has no idea. That’s why blocking one number rarely stops the calls.
- A call from a number almost identical to yours (same 303 and prefix) is “mirror spoofing.” A missed call from your own number is never worth returning.
- Strangers calling you back saying you called them? Your 303 number is being spoofed. It typically passes within days, and you don’t need a new number. Report it at reportfraud.ftc.gov.
- The caller-ID checkmark: AT&T verifies network calls (STIR/SHAKEN). A verified mark means the displayed number wasn’t faked. No mark doesn’t always mean scam, but treat it with more caution.
Spoofed or not, the rule holds: unexpected caller, no voicemail? Let it go.
303 Area Code Prefix & Carrier Lookup
The three digits after the area code identify the carrier a number was issued to. All 784 assigned 303 prefixes below are real, from the public numbering registry. Type to filter.
This isn’t a reverse phone lookup: no legitimate free service can tell you who owns a specific number. What a 303 prefix does show: the carrier that issued it, whether it’s wireless, landline or VoIP, and the community it belongs to, which is often enough to judge whether a call was worth returning.
784 prefixes · updated monthly
| Prefix | Carrier | Line type |
|---|---|---|
| 303-200 | AT&T (Teleport Communications) | Landline |
| 303-201 | Spok (paging) | Landline |
| 303-202 | Qwest Corporation | Landline |
| 303-203 | American Messaging (paging) | Landline |
| 303-204 | Verizon Wireless | Wireless |
| 303-205 | Qwest Corporation | Landline |
| 303-206 | Spok (paging) | Landline |
| 303-207 | Spok (paging) | Landline |
| 303-208 | Spok (paging) | Landline |
| 303-209 | Verizon Business (MCImetro) | Landline |
| 303-210 | T-Mobile | Wireless |
| 303-212 | American Messaging (paging) | Landline |
| 303-213 | Spok (paging) | Landline |
| 303-214 | Verizon Business (MCImetro) | Landline |
| 303-215 | Qwest Corporation | Landline |
| 303-216 | Qwest Corporation | Landline |
| 303-217 | Verizon Business (MCImetro) | Landline |
| 303-218 | Verizon Business (MCImetro) | Landline |
| 303-219 | Verizon Business (MCImetro) | Landline |
| 303-220 | Qwest Corporation | Landline |
| 303-221 | Qwest Corporation | Landline |
| 303-222 | Verizon Business (MCImetro) | Landline |
| 303-223 | Lumen (Level 3) | VoIP |
| 303-224 | Qwest Corporation | Landline |
| 303-225 | Lumen (Level 3) | VoIP |
| 303-226 | Lumen (Level 3) | VoIP |
| 303-227 | Qwest Corporation | Landline |
| 303-228 | Lumen (Level 3) | VoIP |
| 303-229 | Verizon Wireless | Wireless |
| 303-230 | Spok (paging) | Landline |
| 303-231 | Qwest Corporation | Landline |
| 303-232 | Qwest Corporation | Landline |
| 303-233 | Qwest Corporation | Landline |
| 303-234 | Qwest Corporation | Landline |
| 303-235 | Qwest Corporation | Landline |
| 303-236 | Qwest Corporation | Landline |
| 303-237 | Qwest Corporation | Landline |
| 303-238 | Qwest Corporation | Landline |
| 303-239 | Qwest Corporation | Landline |
| 303-240 | Spok (paging) | Landline |
| 303-241 | Verizon Wireless | Wireless |
| 303-242 | Verizon Business (MCImetro) | Landline |
| 303-243 | N.E. Colorado Cellular | Wireless |
| 303-244 | Qwest Corporation | Landline |
| 303-245 | Qwest Corporation | Landline |
| 303-246 | T-Mobile | Wireless |
| 303-247 | Qwest Corporation | Landline |
| 303-248 | AT&T (Teleport Communications) | Landline |
| 303-249 | AT&T Mobility | Wireless |
| 303-250 | AT&T Mobility | Wireless |
| 303-251 | Spok (paging) | Landline |
| 303-252 | Qwest Corporation | Landline |
| 303-253 | AT&T (Teleport Communications) | Landline |
| 303-254 | Qwest Corporation | Landline |
| 303-255 | Qwest Corporation | Landline |
| 303-256 | AT&T (Teleport Communications) | Landline |
| 303-257 | T-Mobile | Wireless |
| 303-258 | Qwest Corporation | Landline |
| 303-259 | American Messaging (paging) | Landline |
| 303-260 | Qwest Corporation | Landline |
| 303-261 | Qwest Corporation | Landline |
| 303-262 | AT&T (Teleport Communications) | Landline |
| 303-263 | Verizon Wireless | Wireless |
| 303-264 | AT&T (Teleport Communications) | Landline |
| 303-265 | Qwest Corporation | Landline |
| 303-266 | Spok (paging) | Landline |
| 303-267 | Qwest Corporation | Landline |
| 303-268 | Lumen (Level 3) | VoIP |
| 303-269 | Qwest Corporation | Landline |
| 303-270 | Qwest Corporation | Landline |
| 303-271 | Qwest Corporation | Landline |
| 303-272 | Qwest Corporation | Landline |
| 303-273 | Qwest Corporation | Landline |
| 303-274 | Qwest Corporation | Landline |
| 303-275 | Qwest Corporation | Landline |
| 303-276 | Onvoy (Sinch) | VoIP |
| 303-277 | Qwest Corporation | Landline |
| 303-278 | Qwest Corporation | Landline |
| 303-279 | Qwest Corporation | Landline |
| 303-280 | Qwest Corporation | Landline |
| 303-281 | Qwest Corporation | Landline |
| 303-282 | Qwest Corporation | Landline |
| 303-283 | Qwest Corporation | Landline |
| 303-284 | Comcast (Xfinity Voice) | VoIP |
| 303-285 | Lumen (Level 3) | VoIP |
| 303-286 | Qwest Corporation | Landline |
| 303-287 | Qwest Corporation | Landline |
| 303-288 | Qwest Corporation | Landline |
| 303-289 | Qwest Corporation | Landline |
| 303-290 | Qwest Corporation | Landline |
| 303-291 | Qwest Corporation | Landline |
| 303-292 | Qwest Corporation | Landline |
| 303-293 | Qwest Corporation | Landline |
| 303-294 | Qwest Corporation | Landline |
| 303-295 | Qwest Corporation | Landline |
| 303-296 | Qwest Corporation | Landline |
| 303-297 | Qwest Corporation | Landline |
| 303-298 | Qwest Corporation | Landline |
| 303-299 | Qwest Corporation | Landline |
| 303-300 | Qwest Corporation | Landline |
| 303-301 | Lumen (Level 3) | VoIP |
| 303-302 | Verizon Business (MCImetro) | Landline |
| 303-303 | Hd Carrier | Landline |
| 303-304 | AT&T Mobility | Wireless |
| 303-305 | Verizon Business (MCImetro) | Landline |
| 303-306 | Qwest Corporation | Landline |
| 303-307 | Qwest Corporation | Landline |
| 303-308 | Qwest Corporation | Landline |
| 303-309 | Lumen (Level 3) | VoIP |
| 303-310 | American Messaging (paging) | Landline |
| 303-312 | Qwest Corporation | Landline |
| 303-313 | Qwest Corporation | Landline |
| 303-314 | Qwest Corporation | Landline |
| 303-315 | Qwest Corporation | Landline |
| 303-316 | Qwest Corporation | Landline |
| 303-317 | Qwest Corporation | Landline |
| 303-318 | Qwest Corporation | Landline |
| 303-319 | Elbert County Wireless | Wireless |
| 303-320 | Qwest Corporation | Landline |
| 303-321 | Qwest Corporation | Landline |
| 303-322 | Qwest Corporation | Landline |
| 303-323 | Verizon Business (MCImetro) | Landline |
| 303-324 | AT&T Mobility | Wireless |
| 303-325 | Lumen (Level 3) | VoIP |
| 303-326 | Qwest Corporation | Landline |
| 303-327 | Lumen (Level 3) | VoIP |
| 303-328 | Verizon Business (MCImetro) | Landline |
| 303-329 | Qwest Corporation | Landline |
| 303-330 | Onvoy (Sinch) | VoIP |
| 303-331 | Qwest Corporation | Landline |
| 303-332 | T-Mobile | Wireless |
| 303-333 | Qwest Corporation | Landline |
| 303-334 | Verizon Business (MCImetro) | Landline |
| 303-335 | Verizon Wireless | Wireless |
| 303-336 | Qwest Corporation | Landline |
| 303-337 | Qwest Corporation | Landline |
| 303-338 | Qwest Corporation | Landline |
| 303-339 | Onvoy (Sinch) | VoIP |
| 303-340 | Qwest Corporation | Landline |
| 303-341 | Qwest Corporation | Landline |
| 303-342 | Qwest Corporation | Landline |
| 303-343 | Qwest Corporation | Landline |
| 303-344 | Qwest Corporation | Landline |
| 303-345 | Lumen (Level 3) | VoIP |
| 303-346 | Qwest Corporation | Landline |
| 303-347 | Qwest Corporation | Landline |
| 303-348 | Qwest Corporation | Landline |
| 303-349 | Verizon Wireless | Wireless |
| 303-350 | AT&T Mobility | Wireless |
| 303-351 | Onvoy (Sinch) | VoIP |
| 303-352 | Qwest Corporation | Landline |
| 303-353 | Comcast (Xfinity Voice) | VoIP |
| 303-354 | AT&T (Teleport Communications) | Landline |
| 303-355 | Qwest Corporation | Landline |
| 303-356 | T-Mobile | Wireless |
| 303-357 | Verizon Business (MCImetro) | Landline |
| 303-358 | Verizon Wireless | Wireless |
| 303-359 | T-Mobile | Wireless |
| 303-360 | Qwest Corporation | Landline |
| 303-361 | Qwest Corporation | Landline |
| 303-362 | AT&T (Teleport Communications) | Landline |
| 303-363 | Qwest Corporation | Landline |
| 303-364 | Qwest Corporation | Landline |
| 303-365 | Qwest Corporation | Landline |
| 303-366 | Qwest Corporation | Landline |
| 303-367 | Qwest Corporation | Landline |
| 303-368 | Qwest Corporation | Landline |
| 303-369 | Qwest Corporation | Landline |
| 303-370 | Qwest Corporation | Landline |
| 303-371 | Qwest Corporation | Landline |
| 303-372 | Qwest Corporation | Landline |
| 303-373 | Qwest Corporation | Landline |
| 303-374 | AT&T (Teleport Communications) | Landline |
| 303-375 | Qwest Corporation | Landline |
| 303-376 | Lumen (Level 3) | VoIP |
| 303-377 | Qwest Corporation | Landline |
| 303-378 | AT&T Mobility | Wireless |
| 303-379 | AT&T (Teleport Communications) | Landline |
| 303-380 | Qwest Corporation | Landline |
| 303-381 | Lumen (Level 3) | VoIP |
| 303-382 | Qwest Corporation | Landline |
| 303-383 | Qwest Corporation | Landline |
| 303-384 | Qwest Corporation | Landline |
| 303-385 | Lumen (Level 3) | VoIP |
| 303-386 | Lumen (Level 3) | VoIP |
| 303-387 | Qwest Corporation | Landline |
| 303-388 | Qwest Corporation | Landline |
| 303-389 | Qwest Corporation | Landline |
| 303-390 | Verizon Business (MCImetro) | Landline |
| 303-391 | Qwest Corporation | Landline |
| 303-392 | Verizon Wireless | Wireless |
| 303-393 | Qwest Corporation | Landline |
| 303-394 | Qwest Corporation | Landline |
| 303-395 | Lumen (Level 3) | VoIP |
| 303-396 | Live Wire Networks | Landline |
| 303-397 | Qwest Corporation | Landline |
| 303-398 | Qwest Corporation | Landline |
| 303-399 | Qwest Corporation | Landline |
| 303-400 | Qwest Corporation | Landline |
| 303-401 | Qwest Corporation | Landline |
| 303-402 | Qwest Corporation | Landline |
| 303-403 | Qwest Corporation | Landline |
| 303-404 | Qwest Corporation | Landline |
| 303-405 | Qwest Corporation | Landline |
| 303-406 | Lumen (Level 3) | VoIP |
| 303-407 | Onvoy (Sinch) | VoIP |
| 303-408 | AT&T Mobility | Wireless |
| 303-409 | Lumen (Level 3) | VoIP |
| 303-410 | Qwest Corporation | Landline |
| 303-412 | Qwest Corporation | Landline |
| 303-413 | Qwest Corporation | Landline |
| 303-414 | Lumen (Level 3) | VoIP |
| 303-415 | Qwest Corporation | Landline |
| 303-416 | Lumen (Level 3) | VoIP |
| 303-417 | Qwest Corporation | Landline |
| 303-418 | Lumen (Level 3) | VoIP |
| 303-419 | T-Mobile | Wireless |
| 303-420 | Qwest Corporation | Landline |
| 303-421 | Qwest Corporation | Landline |
| 303-422 | Qwest Corporation | Landline |
| 303-423 | Qwest Corporation | Landline |
| 303-424 | Qwest Corporation | Landline |
| 303-425 | Qwest Corporation | Landline |
| 303-426 | Qwest Corporation | Landline |
| 303-427 | Qwest Corporation | Landline |
| 303-428 | Qwest Corporation | Landline |
| 303-429 | Qwest Corporation | Landline |
| 303-430 | Qwest Corporation | Landline |
| 303-431 | Qwest Corporation | Landline |
| 303-432 | Qwest Corporation | Landline |
| 303-433 | Qwest Corporation | Landline |
| 303-434 | T-Mobile | Wireless |
| 303-435 | T-Mobile | Wireless |
| 303-436 | Qwest Corporation | Landline |
| 303-437 | T-Mobile | Wireless |
| 303-438 | Qwest Corporation | Landline |
| 303-439 | Qwest Corporation | Landline |
| 303-440 | Qwest Corporation | Landline |
| 303-441 | Qwest Corporation | Landline |
| 303-442 | Qwest Corporation | Landline |
| 303-443 | Qwest Corporation | Landline |
| 303-444 | Qwest Corporation | Landline |
| 303-445 | Qwest Corporation | Landline |
| 303-446 | Qwest Corporation | Landline |
| 303-447 | Qwest Corporation | Landline |
| 303-448 | Qwest Corporation | Landline |
| 303-449 | Qwest Corporation | Landline |
| 303-450 | Qwest Corporation | Landline |
| 303-451 | Qwest Corporation | Landline |
| 303-452 | Qwest Corporation | Landline |
| 303-453 | Qwest Corporation | Landline |
| 303-454 | Qwest Corporation | Landline |
| 303-455 | Qwest Corporation | Landline |
| 303-456 | Qwest Corporation | Landline |
| 303-457 | Qwest Corporation | Landline |
| 303-458 | Qwest Corporation | Landline |
| 303-459 | Qwest Corporation | Landline |
| 303-460 | Qwest Corporation | Landline |
| 303-461 | Spok (paging) | Landline |
| 303-462 | Qwest Corporation | Landline |
| 303-463 | Qwest Corporation | Landline |
| 303-464 | Qwest Corporation | Landline |
| 303-465 | Qwest Corporation | Landline |
| 303-466 | Qwest Corporation | Landline |
| 303-467 | Qwest Corporation | Landline |
| 303-468 | Onvoy (Sinch) | VoIP |
| 303-469 | Qwest Corporation | Landline |
| 303-470 | Qwest Corporation | Landline |
| 303-471 | Qwest Corporation | Landline |
| 303-472 | T-Mobile | Wireless |
| 303-473 | Qwest Corporation | Landline |
| 303-474 | AT&T (Teleport Communications) | Landline |
| 303-475 | AT&T Mobility | Wireless |
| 303-476 | Verizon Business (MCImetro) | Landline |
| 303-477 | Qwest Corporation | Landline |
| 303-478 | AT&T Mobility | Wireless |
| 303-479 | AT&T (Teleport Communications) | Landline |
| 303-480 | Qwest Corporation | Landline |
| 303-481 | Verizon Business (MCImetro) | Landline |
| 303-482 | Lumen (Level 3) | VoIP |
| 303-483 | Lumen (Level 3) | VoIP |
| 303-484 | AT&T (Teleport Communications) | Landline |
| 303-485 | Qwest Corporation | Landline |
| 303-486 | Qwest Corporation | Landline |
| 303-487 | Qwest Corporation | Landline |
| 303-488 | Qwest Corporation | Landline |
| 303-489 | Verizon Wireless | Wireless |
| 303-490 | Spok (paging) | Landline |
| 303-491 | Onvoy Spectrum (Sinch) | VoIP |
| 303-492 | Qwest Corporation | Landline |
| 303-493 | Lumen (Level 3) | VoIP |
| 303-494 | Qwest Corporation | Landline |
| 303-495 | Verizon Business (MCImetro) | Landline |
| 303-496 | Verizon Business (MCImetro) | Landline |
| 303-497 | Qwest Corporation | Landline |
| 303-498 | Comcast (Xfinity Voice) | VoIP |
| 303-499 | Qwest Corporation | Landline |
| 303-500 | Lumen (Level 3) | VoIP |
| 303-501 | Verizon Wireless | Wireless |
| 303-502 | Verizon Wireless | Wireless |
| 303-503 | Verizon Wireless | Wireless |
| 303-504 | Qwest Corporation | Landline |
| 303-505 | T-Mobile | Wireless |
| 303-506 | AT&T Mobility | Wireless |
| 303-507 | T-Mobile | Wireless |
| 303-508 | American Messaging (paging) | Landline |
| 303-509 | American Messaging (paging) | Landline |
| 303-510 | American Messaging (paging) | Landline |
| 303-512 | Qwest Corporation | Landline |
| 303-513 | AT&T Mobility | Wireless |
| 303-514 | Verizon Wireless | Wireless |
| 303-515 | Onvoy (Sinch) | VoIP |
| 303-516 | Qwest Corporation | Landline |
| 303-517 | AT&T Mobility | Wireless |
| 303-518 | Verizon Wireless | Wireless |
| 303-519 | Verizon Wireless | Wireless |
| 303-520 | T-Mobile | Wireless |
| 303-521 | T-Mobile | Wireless |
| 303-522 | T-Mobile | Wireless |
| 303-523 | T-Mobile | Wireless |
| 303-524 | AT&T (Teleport Communications) | Landline |
| 303-525 | T-Mobile | Wireless |
| 303-526 | Qwest Corporation | Landline |
| 303-527 | Qwest Corporation | Landline |
| 303-528 | American Messaging (paging) | Landline |
| 303-529 | Onvoy (Sinch) | VoIP |
| 303-530 | Qwest Corporation | Landline |
| 303-531 | Verizon Business (MCImetro) | Landline |
| 303-532 | Windstream (Paetec) | Landline |
| 303-533 | Qwest Corporation | Landline |
| 303-534 | Qwest Corporation | Landline |
| 303-535 | Onvoy (Sinch) | VoIP |
| 303-536 | Qwest Corporation | Landline |
| 303-537 | AT&T (Teleport Communications) | Landline |
| 303-538 | Qwest Corporation | Landline |
| 303-539 | Verizon Business (MCImetro) | Landline |
| 303-540 | Spok (paging) | Landline |
| 303-541 | Qwest Corporation | Landline |
| 303-542 | Verizon Business (MCImetro) | Landline |
| 303-543 | Qwest Corporation | Landline |
| 303-544 | Qwest Corporation | Landline |
| 303-545 | Qwest Corporation | Landline |
| 303-546 | Qwest Corporation | Landline |
| 303-547 | Lumen (Level 3) | VoIP |
| 303-548 | Verizon Wireless | Wireless |
| 303-549 | Verizon Wireless | Wireless |
| 303-550 | Verizon Wireless | Wireless |
| 303-551 | Verizon Business (MCImetro) | Landline |
| 303-552 | Lumen (Level 3) | VoIP |
| 303-553 | Spok (paging) | Landline |
| 303-554 | Qwest Corporation | Landline |
| 303-556 | Qwest Corporation | Landline |
| 303-557 | Lumen (Level 3) | VoIP |
| 303-558 | Lumen (Level 3) | VoIP |
| 303-559 | American Messaging (paging) | Landline |
| 303-560 | Spok (paging) | Landline |
| 303-561 | Qwest Corporation | Landline |
| 303-562 | Lumen (Level 3) | VoIP |
| 303-563 | Lumen (Level 3) | VoIP |
| 303-564 | T-Mobile | Wireless |
| 303-565 | Onvoy (Sinch) | VoIP |
| 303-566 | Verizon Business (MCImetro) | Landline |
| 303-567 | Qwest Corporation | Landline |
| 303-568 | AT&T (Teleport Communications) | Landline |
| 303-569 | Qwest Corporation | Landline |
| 303-570 | AT&T Mobility | Wireless |
| 303-571 | Qwest Corporation | Landline |
| 303-572 | Qwest Corporation | Landline |
| 303-573 | Qwest Corporation | Landline |
| 303-574 | Qwest Corporation | Landline |
| 303-575 | Qwest Corporation | Landline |
| 303-576 | Qwest Corporation | Landline |
| 303-577 | Allstream (Electric Lightwave) | Landline |
| 303-578 | Lumen (Level 3) | VoIP |
| 303-579 | Verizon Wireless | Wireless |
| 303-580 | American Messaging (paging) | Landline |
| 303-581 | Qwest Corporation | Landline |
| 303-582 | Qwest Corporation | Landline |
| 303-583 | AT&T (Teleport Communications) | Landline |
| 303-584 | Qwest Corporation | Landline |
| 303-585 | Qwest Corporation | Landline |
| 303-586 | Lumen (Level 3) | VoIP |
| 303-587 | T-Mobile | Wireless |
| 303-588 | AT&T Mobility | Wireless |
| 303-589 | AT&T Mobility | Wireless |
| 303-590 | Lumen (Level 3) | VoIP |
| 303-591 | T-Mobile | Wireless |
| 303-592 | Qwest Corporation | Landline |
| 303-593 | AT&T (Teleport Communications) | Landline |
| 303-594 | Verizon Wireless | Wireless |
| 303-595 | Qwest Corporation | Landline |
| 303-596 | T-Mobile | Wireless |
| 303-597 | Allstream (Electric Lightwave) | Landline |
| 303-598 | T-Mobile | Wireless |
| 303-599 | Spok (paging) | Landline |
| 303-600 | AT&T (Teleport Communications) | Landline |
| 303-601 | AT&T Mobility | Wireless |
| 303-602 | Qwest Corporation | Landline |
| 303-603 | Qwest Corporation | Landline |
| 303-604 | Qwest Corporation | Landline |
| 303-605 | Qwest Corporation | Landline |
| 303-606 | Qwest Corporation | Landline |
| 303-607 | Qwest Corporation | Landline |
| 303-608 | Qwest Corporation | Landline |
| 303-609 | Spok (paging) | Landline |
| 303-610 | Spok (paging) | Landline |
| 303-612 | Spok (paging) | Landline |
| 303-613 | Spok (paging) | Landline |
| 303-614 | Qwest Corporation | Landline |
| 303-615 | Qwest Corporation | Landline |
| 303-616 | Onvoy Spectrum (Sinch) | VoIP |
| 303-617 | Qwest Corporation | Landline |
| 303-618 | AT&T Mobility | Wireless |
| 303-619 | AT&T Mobility | Wireless |
| 303-620 | Qwest Corporation | Landline |
| 303-621 | Qwest Corporation | Landline |
| 303-622 | Strasburg Tel. | Landline |
| 303-623 | Qwest Corporation | Landline |
| 303-624 | Qwest Corporation | Landline |
| 303-625 | Lumen (Level 3) | VoIP |
| 303-626 | Qwest Corporation | Landline |
| 303-627 | Qwest Corporation | Landline |
| 303-628 | Qwest Corporation | Landline |
| 303-629 | Qwest Corporation | Landline |
| 303-630 | Qwest Corporation | Landline |
| 303-632 | AT&T (Teleport Communications) | Landline |
| 303-633 | Qwest Corporation | Landline |
| 303-634 | Qwest Corporation | Landline |
| 303-635 | Qwest Corporation | Landline |
| 303-636 | Qwest Corporation | Landline |
| 303-637 | Qwest Corporation | Landline |
| 303-638 | AT&T Mobility | Wireless |
| 303-639 | Qwest Corporation | Landline |
| 303-640 | Qwest Corporation | Landline |
| 303-641 | T-Mobile | Wireless |
| 303-642 | Qwest Corporation | Landline |
| 303-643 | Qwest Corporation | Landline |
| 303-644 | Eastern Slope Rural Tel. Assn. | Landline |
| 303-645 | Qwest Corporation | Landline |
| 303-646 | Qwest Corporation | Landline |
| 303-647 | Qwest Corporation | Landline |
| 303-648 | Qwest Corporation | Landline |
| 303-649 | Qwest Corporation | Landline |
| 303-650 | Qwest Corporation | Landline |
| 303-651 | Qwest Corporation | Landline |
| 303-652 | Qwest Corporation | Landline |
| 303-653 | Lumen (Level 3) | VoIP |
| 303-654 | Qwest Corporation | Landline |
| 303-655 | Qwest Corporation | Landline |
| 303-656 | Verizon Wireless | Wireless |
| 303-657 | Qwest Corporation | Landline |
| 303-658 | Qwest Corporation | Landline |
| 303-659 | Qwest Corporation | Landline |
| 303-660 | Qwest Corporation | Landline |
| 303-661 | Qwest Corporation | Landline |
| 303-662 | Qwest Corporation | Landline |
| 303-663 | Qwest Corporation | Landline |
| 303-664 | Qwest Corporation | Landline |
| 303-665 | Qwest Corporation | Landline |
| 303-666 | Qwest Corporation | Landline |
| 303-667 | T-Mobile | Wireless |
| 303-668 | T-Mobile | Wireless |
| 303-669 | T-Mobile | Wireless |
| 303-670 | Qwest Corporation | Landline |
| 303-671 | Qwest Corporation | Landline |
| 303-672 | Qwest Corporation | Landline |
| 303-673 | Qwest Corporation | Landline |
| 303-674 | Qwest Corporation | Landline |
| 303-675 | Qwest Corporation | Landline |
| 303-676 | Qwest Corporation | Landline |
| 303-677 | Qwest Corporation | Landline |
| 303-678 | Qwest Corporation | Landline |
| 303-679 | Qwest Corporation | Landline |
| 303-680 | Qwest Corporation | Landline |
| 303-681 | Qwest Corporation | Landline |
| 303-682 | Qwest Corporation | Landline |
| 303-683 | Qwest Corporation | Landline |
| 303-684 | Qwest Corporation | Landline |
| 303-685 | Qwest Corporation | Landline |
| 303-686 | Spok (paging) | Landline |
| 303-687 | Spok (paging) | Landline |
| 303-688 | Qwest Corporation | Landline |
| 303-689 | Qwest Corporation | Landline |
| 303-690 | Qwest Corporation | Landline |
| 303-691 | Qwest Corporation | Landline |
| 303-692 | Qwest Corporation | Landline |
| 303-693 | Qwest Corporation | Landline |
| 303-694 | Qwest Corporation | Landline |
| 303-695 | Qwest Corporation | Landline |
| 303-696 | Qwest Corporation | Landline |
| 303-697 | Qwest Corporation | Landline |
| 303-698 | Qwest Corporation | Landline |
| 303-699 | Qwest Corporation | Landline |
| 303-701 | Communications Unlimited | Landline |
| 303-702 | Qwest Corporation | Landline |
| 303-703 | Qwest Corporation | Landline |
| 303-704 | Verizon Business (MCImetro) | Landline |
| 303-705 | Qwest Corporation | Landline |
| 303-706 | Qwest Corporation | Landline |
| 303-707 | Qwest Corporation | Landline |
| 303-708 | Qwest Corporation | Landline |
| 303-709 | Verizon Wireless | Wireless |
| 303-710 | Verizon Wireless | Wireless |
| 303-712 | Qwest Corporation | Landline |
| 303-713 | Qwest Corporation | Landline |
| 303-714 | Qwest Corporation | Landline |
| 303-715 | Qwest Corporation | Landline |
| 303-716 | Qwest Corporation | Landline |
| 303-717 | AT&T Mobility | Wireless |
| 303-718 | Verizon Wireless | Wireless |
| 303-719 | Lumen (Level 3) | VoIP |
| 303-720 | Verizon Wireless | Wireless |
| 303-721 | Qwest Corporation | Landline |
| 303-722 | Qwest Corporation | Landline |
| 303-723 | AT&T (Teleport Communications) | Landline |
| 303-724 | Qwest Corporation | Landline |
| 303-725 | T-Mobile | Wireless |
| 303-726 | Verizon Wireless | Wireless |
| 303-727 | Qwest Corporation | Landline |
| 303-728 | AT&T (Teleport Communications) | Landline |
| 303-729 | Verizon Business (MCImetro) | Landline |
| 303-730 | Qwest Corporation | Landline |
| 303-731 | Lumen (Level 3) | VoIP |
| 303-732 | Qwest Corporation | Landline |
| 303-733 | Qwest Corporation | Landline |
| 303-734 | Qwest Corporation | Landline |
| 303-735 | Qwest Corporation | Landline |
| 303-736 | AT&T (Teleport Communications) | Landline |
| 303-737 | Qwest Corporation | Landline |
| 303-738 | Qwest Corporation | Landline |
| 303-739 | Qwest Corporation | Landline |
| 303-740 | Qwest Corporation | Landline |
| 303-741 | Qwest Corporation | Landline |
| 303-742 | Qwest Corporation | Landline |
| 303-743 | Qwest Corporation | Landline |
| 303-744 | Qwest Corporation | Landline |
| 303-745 | Qwest Corporation | Landline |
| 303-746 | Verizon Wireless | Wireless |
| 303-747 | Qwest Corporation | Landline |
| 303-748 | AT&T Mobility | Wireless |
| 303-749 | AT&T (Teleport Communications) | Landline |
| 303-750 | Qwest Corporation | Landline |
| 303-751 | Qwest Corporation | Landline |
| 303-752 | Qwest Corporation | Landline |
| 303-753 | Qwest Corporation | Landline |
| 303-754 | Qwest Corporation | Landline |
| 303-755 | Qwest Corporation | Landline |
| 303-756 | Qwest Corporation | Landline |
| 303-757 | Qwest Corporation | Landline |
| 303-758 | Qwest Corporation | Landline |
| 303-759 | Qwest Corporation | Landline |
| 303-760 | Spok (paging) | Landline |
| 303-761 | Qwest Corporation | Landline |
| 303-762 | Qwest Corporation | Landline |
| 303-763 | Qwest Corporation | Landline |
| 303-764 | Qwest Corporation | Landline |
| 303-765 | Qwest Corporation | Landline |
| 303-766 | Qwest Corporation | Landline |
| 303-767 | American Messaging (paging) | Landline |
| 303-768 | Qwest Corporation | Landline |
| 303-769 | Bijou Tel. Coop. Assn. | Landline |
| 303-770 | Qwest Corporation | Landline |
| 303-771 | Qwest Corporation | Landline |
| 303-772 | Qwest Corporation | Landline |
| 303-773 | Qwest Corporation | Landline |
| 303-774 | Qwest Corporation | Landline |
| 303-775 | Verizon Wireless | Wireless |
| 303-776 | Qwest Corporation | Landline |
| 303-777 | Qwest Corporation | Landline |
| 303-778 | Qwest Corporation | Landline |
| 303-779 | Qwest Corporation | Landline |
| 303-780 | Qwest Corporation | Landline |
| 303-781 | Qwest Corporation | Landline |
| 303-782 | Qwest Corporation | Landline |
| 303-783 | Qwest Corporation | Landline |
| 303-784 | Qwest Corporation | Landline |
| 303-785 | Verizon Business (MCImetro) | Landline |
| 303-786 | Qwest Corporation | Landline |
| 303-787 | Qwest Corporation | Landline |
| 303-788 | Qwest Corporation | Landline |
| 303-789 | Qwest Corporation | Landline |
| 303-790 | Qwest Corporation | Landline |
| 303-791 | Qwest Corporation | Landline |
| 303-792 | Qwest Corporation | Landline |
| 303-793 | Qwest Corporation | Landline |
| 303-794 | Qwest Corporation | Landline |
| 303-795 | Qwest Corporation | Landline |
| 303-796 | Qwest Corporation | Landline |
| 303-797 | Qwest Corporation | Landline |
| 303-798 | Qwest Corporation | Landline |
| 303-799 | Qwest Corporation | Landline |
| 303-800 | Lumen (Level 3) | VoIP |
| 303-801 | Verizon Business (MCImetro) | Landline |
| 303-802 | Lumen (Level 3) | VoIP |
| 303-803 | Lumen (Level 3) | VoIP |
| 303-804 | Qwest Corporation | Landline |
| 303-805 | Qwest Corporation | Landline |
| 303-806 | Qwest Corporation | Landline |
| 303-807 | AT&T Mobility | Wireless |
| 303-808 | AT&T Mobility | Wireless |
| 303-809 | AT&T Mobility | Wireless |
| 303-810 | AT&T Mobility | Wireless |
| 303-812 | Qwest Corporation | Landline |
| 303-813 | Qwest Corporation | Landline |
| 303-814 | Qwest Corporation | Landline |
| 303-815 | Interlink Adv Svc dba Forethought.Net | Landline |
| 303-816 | Qwest Corporation | Landline |
| 303-817 | Verizon Wireless | Wireless |
| 303-818 | Verizon Wireless | Wireless |
| 303-819 | Verizon Wireless | Wireless |
| 303-820 | Qwest Corporation | Landline |
| 303-821 | Spok (paging) | Landline |
| 303-822 | Bijou Tel. Coop. Assn. | Landline |
| 303-823 | Qwest Corporation | Landline |
| 303-824 | AT&T (Teleport Communications) | Landline |
| 303-825 | Qwest Corporation | Landline |
| 303-826 | Spok (paging) | Landline |
| 303-827 | Lumen (Level 3) | VoIP |
| 303-828 | Qwest Corporation | Landline |
| 303-829 | Verizon Wireless | Wireless |
| 303-830 | Qwest Corporation | Landline |
| 303-831 | Qwest Corporation | Landline |
| 303-832 | Qwest Corporation | Landline |
| 303-833 | Qwest Corporation | Landline |
| 303-834 | Verizon Wireless | Wireless |
| 303-835 | Lumen (Level 3) | VoIP |
| 303-836 | Communications Unlimited | Landline |
| 303-837 | Qwest Corporation | Landline |
| 303-838 | Qwest Corporation | Landline |
| 303-839 | Qwest Corporation | Landline |
| 303-840 | Qwest Corporation | Landline |
| 303-841 | Qwest Corporation | Landline |
| 303-842 | Verizon Wireless | Wireless |
| 303-843 | Qwest Corporation | Landline |
| 303-844 | Qwest Corporation | Landline |
| 303-845 | AT&T (Teleport Communications) | Landline |
| 303-846 | Qwest Corporation | Landline |
| 303-847 | Lumen (Level 3) | VoIP |
| 303-848 | Lumen (Level 3) | VoIP |
| 303-849 | Roggen Tel. Coop. | Landline |
| 303-850 | Qwest Corporation | Landline |
| 303-851 | Spok (paging) | Landline |
| 303-852 | Spok (paging) | Landline |
| 303-853 | Qwest Corporation | Landline |
| 303-854 | Lumen (Level 3) | VoIP |
| 303-855 | Spok (paging) | Landline |
| 303-856 | Lumen (Level 3) | VoIP |
| 303-857 | Qwest Corporation | Landline |
| 303-858 | Qwest Corporation | Landline |
| 303-859 | Verizon Wireless | Wireless |
| 303-860 | Qwest Corporation | Landline |
| 303-861 | Qwest Corporation | Landline |
| 303-862 | Comcast (Xfinity Voice) | VoIP |
| 303-863 | Qwest Corporation | Landline |
| 303-864 | Qwest Corporation | Landline |
| 303-865 | Lumen (Level 3) | VoIP |
| 303-866 | Qwest Corporation | Landline |
| 303-867 | Iloka, Inc. dba Newcloud Networks | Landline |
| 303-868 | Verizon Wireless | Wireless |
| 303-869 | Qwest Corporation | Landline |
| 303-870 | Verizon Wireless | Wireless |
| 303-871 | Qwest Corporation | Landline |
| 303-872 | Lumen (Level 3) | VoIP |
| 303-873 | Qwest Corporation | Landline |
| 303-874 | Lumen (Level 3) | VoIP |
| 303-875 | T-Mobile | Wireless |
| 303-876 | Verizon Business (MCImetro) | Landline |
| 303-877 | Verizon Wireless | Wireless |
| 303-878 | Spok (paging) | Landline |
| 303-879 | Onvoy (Sinch) | VoIP |
| 303-880 | Verizon Wireless | Wireless |
| 303-881 | AT&T Mobility | Wireless |
| 303-882 | AT&T Mobility | Wireless |
| 303-883 | AT&T Mobility | Wireless |
| 303-884 | AT&T Mobility | Wireless |
| 303-885 | AT&T Mobility | Wireless |
| 303-886 | AT&T Mobility | Wireless |
| 303-887 | AT&T Mobility | Wireless |
| 303-888 | AT&T Mobility | Wireless |
| 303-889 | Qwest Corporation | Landline |
| 303-890 | Spok (paging) | Landline |
| 303-891 | Spok (paging) | Landline |
| 303-892 | Qwest Corporation | Landline |
| 303-893 | Qwest Corporation | Landline |
| 303-894 | Qwest Corporation | Landline |
| 303-895 | Verizon Wireless | Wireless |
| 303-896 | Qwest Corporation | Landline |
| 303-897 | Spok (paging) | Landline |
| 303-898 | AT&T Mobility | Wireless |
| 303-899 | Qwest Corporation | Landline |
| 303-900 | Lumen (Level 3) | VoIP |
| 303-901 | T-Mobile | Wireless |
| 303-902 | Verizon Wireless | Wireless |
| 303-903 | Verizon Wireless | Wireless |
| 303-904 | Qwest Corporation | Landline |
| 303-905 | Verizon Wireless | Wireless |
| 303-906 | Verizon Wireless | Wireless |
| 303-907 | Verizon Wireless | Wireless |
| 303-908 | Verizon Wireless | Wireless |
| 303-909 | Verizon Wireless | Wireless |
| 303-910 | Verizon Wireless | Wireless |
| 303-912 | Verizon Wireless | Wireless |
| 303-913 | Verizon Wireless | Wireless |
| 303-914 | Qwest Corporation | Landline |
| 303-915 | Verizon Wireless | Wireless |
| 303-916 | Verizon Wireless | Wireless |
| 303-917 | Verizon Wireless | Wireless |
| 303-918 | Verizon Wireless | Wireless |
| 303-919 | Verizon Wireless | Wireless |
| 303-920 | Qwest Corporation | Landline |
| 303-921 | Verizon Wireless | Wireless |
| 303-922 | Qwest Corporation | Landline |
| 303-923 | Lumen (Level 3) | VoIP |
| 303-924 | Qwest Corporation | Landline |
| 303-925 | Qwest Corporation | Landline |
| 303-926 | Qwest Corporation | Landline |
| 303-927 | AT&T (Teleport Communications) | Landline |
| 303-928 | Verizon Business (MCImetro) | Landline |
| 303-929 | Verizon Wireless | Wireless |
| 303-930 | Qwest Corporation | Landline |
| 303-931 | T-Mobile | Wireless |
| 303-932 | Qwest Corporation | Landline |
| 303-933 | Qwest Corporation | Landline |
| 303-934 | Qwest Corporation | Landline |
| 303-935 | Qwest Corporation | Landline |
| 303-936 | Qwest Corporation | Landline |
| 303-937 | Qwest Corporation | Landline |
| 303-938 | Qwest Corporation | Landline |
| 303-939 | Qwest Corporation | Landline |
| 303-940 | Qwest Corporation | Landline |
| 303-941 | Verizon Wireless | Wireless |
| 303-942 | AT&T (Teleport Communications) | Landline |
| 303-943 | Skye Telecom LLC dba Skyetel | Landline |
| 303-944 | T-Mobile | Wireless |
| 303-945 | Comcast (Xfinity Voice) | VoIP |
| 303-946 | T-Mobile | Wireless |
| 303-947 | Verizon Wireless | Wireless |
| 303-948 | Qwest Corporation | Landline |
| 303-949 | T-Mobile | Wireless |
| 303-951 | Lumen (Level 3) | VoIP |
| 303-952 | Lumen (Level 3) | VoIP |
| 303-953 | Lumen (Level 3) | VoIP |
| 303-954 | Lumen (Level 3) | VoIP |
| 303-955 | Lumen (Level 3) | VoIP |
| 303-956 | AT&T Mobility | Wireless |
| 303-957 | Lumen (Level 3) | VoIP |
| 303-960 | T-Mobile | Wireless |
| 303-961 | T-Mobile | Wireless |
| 303-962 | Onvoy (Sinch) | VoIP |
| 303-963 | Lumen (Level 3) | VoIP |
| 303-964 | Qwest Corporation | Landline |
| 303-965 | Qwest Corporation | Landline |
| 303-966 | Qwest Corporation | Landline |
| 303-967 | Qwest Corporation | Landline |
| 303-968 | Verizon Business (MCImetro) | Landline |
| 303-969 | Qwest Corporation | Landline |
| 303-970 | Onvoy (Sinch) | VoIP |
| 303-971 | Qwest Corporation | Landline |
| 303-972 | Qwest Corporation | Landline |
| 303-973 | Qwest Corporation | Landline |
| 303-974 | Lumen (Level 3) | VoIP |
| 303-975 | Qwest Corporation | Landline |
| 303-977 | Qwest Corporation | Landline |
| 303-978 | Qwest Corporation | Landline |
| 303-979 | Qwest Corporation | Landline |
| 303-980 | Qwest Corporation | Landline |
| 303-981 | Verizon Wireless | Wireless |
| 303-982 | Qwest Corporation | Landline |
| 303-984 | Qwest Corporation | Landline |
| 303-985 | Qwest Corporation | Landline |
| 303-986 | Qwest Corporation | Landline |
| 303-987 | Qwest Corporation | Landline |
| 303-988 | Qwest Corporation | Landline |
| 303-989 | Qwest Corporation | Landline |
| 303-990 | T-Mobile | Wireless |
| 303-991 | Verizon Business (MCImetro) | Landline |
| 303-992 | Qwest Corporation | Landline |
| 303-993 | Onvoy (Sinch) | VoIP |
| 303-994 | T-Mobile | Wireless |
| 303-995 | T-Mobile | Wireless |
| 303-996 | Allstream (Electric Lightwave) | Landline |
| 303-997 | Comcast (Xfinity Voice) | VoIP |
| 303-998 | Qwest Corporation | Landline |
| 303-999 | Comcast (Xfinity Voice) | VoIP |
Line type reflects the registry assignment; ported numbers can differ. Unknown 303 number calling? ActiveArmor® screens it before you ever look it up.
Cities & Communities in and around Area Code 303
Communities the 303 serves, filtered against the numbering registry’s rate centers, with each community’s key ZIP codes and the AT&T home internet available there. Cities link to their local AT&T internet page.
| City / community | Key ZIP codes | AT&T internet |
|---|---|---|
| Arvada | 80005, 80004, 80007 | Fiber up to 1 GIG |
| Aurora | 80018, 80017, 80013 | Fiber up to 1 GIG |
| Bennett | 80102 | Check address |
| Berthoud | 80534, 80542, 80543 | Fiber up to 1 GIG |
| Boulder | 80310, 80304, 80301 | Fiber up to 1 GIG |
| Brighton | 80601, 80602, 80640 | Fiber up to 1 GIG |
| Broomfield | 80020, 80023, 80234 | Fiber up to 1 GIG |
| Castle Rock | 80109, 80108, 80104 | Fiber up to 1 GIG |
| Commerce City | 80022, 80640, 80601 | Fiber up to 1 GIG |
| Dacono | 80514, 80530, 80520 | Internet Air |
| Denver | 80238, 80010, 80207 | Fiber up to 1 GIG |
| Edgewater | 80214, 80212, 80204 | Fiber up to 1 GIG |
| Elizabeth | 80107, 80116 | Fiber up to 1 GIG |
| Englewood | 80110, 80113, 80236 | Fiber up to 1 GIG |
| Erie | 80516, 80026, 80023 | Fiber up to 1 GIG |
| Evans | 80620, 80634, 80623 | Fiber up to 1 GIG |
| Evergreen | 80457, 80454, 80439 | Fiber up to 1 GIG |
| Firestone | 80520, 80530, 80504 | Fiber up to 1 GIG |
| Fort Lupton | 80621, 80530, 80520 | Internet Air |
| Franktown | 80116, 80134, 80108 | Fiber up to 1 GIG |
| Frederick | 80520, 80514, 80530 | Fiber up to 1 GIG |
| Golden | 80419, 80401, 80228 | Fiber up to 1 GIG |
| Greeley | 80634, 80620, 80631 | Fiber up to 1 GIG |
| Greenwood Village | 80111, 80237, 80121 | Fiber up to 1 GIG |
| Highlands Ranch | 80126, 80129, 80130 | Fiber up to 1 GIG |
| Hudson | 80642, 80643 | Internet Air |
| Idaho Springs | 80427, 80452, 80436 | Internet Air |
| Indian Hills | 80454, 80453, 80465 | Internet Air |
| Kiowa | 80117, 80107 | Internet Air |
| Kittredge | 80457, 80453, 80454 | Internet Air |
| Lafayette | 80026, 80027, 80020 | Fiber up to 1 GIG |
| Lakewood | 80226, 80232, 80227 | Fiber up to 1 GIG |
| Larkspur | 80118, 80104 | Internet Air |
| Littleton | 80120, 80129, 80123 | Fiber up to 1 GIG |
| Lone Tree | 80124, 80130, 80112 | Fiber up to 1 GIG |
| Longmont | 80501, 80504, 80503 | Fiber up to 1 GIG |
| Louisville | 80027, 80303, 80026 | Fiber up to 1 GIG |
| Loveland | 80528, 80537, 80525 | Fiber up to 1 GIG |
| Lyons | 80503, 80540 | Internet Air |
| Morrison | 80465, 80454, 80453 | Fiber up to 1 GIG |
| Nederland | 80466, 80474, 80471 | Internet Air |
| Niwot | 80544, 80301, 80501 | Fiber up to 1 GIG |
| Parker | 80134, 80138, 80108 | Fiber up to 1 GIG |
| Platteville | 80651, 80623 | Internet Air |
| Sedalia | 80131, 80109, 80125 | Internet Air |
| Sheridan | 80110, 80236, 80113 | Fiber up to 1 GIG |
| Thornton | 80241, 80233, 80234 | Fiber up to 1 GIG |
| Watkins | 80137, 80018, 80102 | Internet Air |
| Westminster | 80031, 80021, 80260 | Fiber up to 1 GIG |
| Wheat Ridge | 80033, 80002, 80215 | Fiber up to 1 GIG |
City list: AT&T service-area records and the public numbering registry. Key ZIPs: U.S. Census data for each community. Internet type: AT&T eligibility data, June 2026. Availability is always confirmed at your exact address.
303 Area Code Map
Area code 303 serves Denver and nearby communities in CO.
↓ Printable PDF
Open the printable 303 map (PDF) · All Colorado area codes · Home internet in Denver
Counties Covered by the 303 Area Code
Counties are served in whole or in part; population is U.S. Census Bureau ACS 2023. The 303 also reaches parts of Larimer County, Douglas County, Boulder County, Weld County, Broomfield County, Elbert County, Clear Creek County.
The 303, explained
Area Code 303: More Than a Number in Denver
In Denver, the 303 is more than digits on a caller ID. It’s one of the original area codes of 1947, and it has meant Denver and surrounding communities ever since — 784 carrier prefixes keep its lines busy today, and an established 303 number still says you’ve been here a while.
The map tells its own story: Denver and surrounding communities, with 720 and 983 sharing the same streets today. Several codes, one local calling area, no long-distance between any of them — only the 303 came first.
Keeping a 303 matters here. An existing 303 number ports to a new phone, a new carrier, or a new AT&T line, and stays yours anywhere in the U.S. New lines in the area often draw 720 instead — one more reason locals hold on to theirs.
Need a new local number? Shop plans Keep your 303: bring it to AT&TInternet, wireless & stores in the 303
AT&T Home Internet in Area Code 303
AT&T home internet serves communities across area code 303, with AT&T Fiber where it’s built and AT&T Internet Air covering the gaps. Availability is decided address by address; every community in the table above links to its local internet page.
No data capsNo annual contractNo equipment fees
AT&T Fiber: Ltd. avail/areas. Speeds based on wired connection. Actual speeds vary. For 5-GIG, single device wired speed maximum 4.7Gbps. For more info., visit att.com/speed101. AT&T Internet Air: AT&T Internet Air not available in all areas. In rare cases, if your usage is contributing to congestion on the network, AT&T will greatly reduce your speed for a minimum of 30 min.
Pair it with wireless in an internet + wireless bundle. Run a business in the 303? AT&T Business Internet is available at many addresses.
Fiber install day in the 303Check your address ›
Moving to Area Code 303?
Set up home internet in area code 303 before the boxes arrive, and find your new community in the table above or check your exact address below.
Your number moves with you: port your 303 number from anywhere, or keep your old number when you arrive. An AT&T store nearby can handle the whole switch in one visit.
1 · Check your addressSee Fiber or Internet Air availability in seconds.
2 · Schedule for move-in dayInstall lined up before the boxes arrive.
3 · Keep your numberYour mobile number ports; your internet moves.
Get set up before move-in dayPlan your move ›
AT&T Wireless in Area Code 303
AT&T’s 5G network covers most of area code 303. ActiveArmor® spam blocking is included with every unlimited plan, your 303 number stays yours, and great cell phone deals in Denver are a tap away.
5G across the 303ActiveArmor® includedKeep your 303 number
AT&T may temporarily slow data speeds if the network is busy. 5G req’s compatible plan & device. Coverage not available everywhere. Learn more at att.com/5Gforyou.
Need a new 303 number? Ask when you activate a line: the 303 shares its territory with 720 and 983, so new lines may draw one of those codes, and porting an existing 303 number keeps it yours.
Stay connected across DenverShop wireless plans ›
AT&T Stores in Area Code 303
Looking for cell phone stores in area code 303? These stores answer on 303 numbers — walk in for switching, porting, upgrades and hands-on help:
Every AT&T store in the region, company owned and authorized retailer alike, each with its own store page.
Real help from real people in DenverFind your store ›
All AT&T Stores with 303 Numbers
Every store below answers on a 303 number. Tap any number to call.
10 AT&T stores with 303 numbers
International Calling from Area Code 303
Calling abroad from area code 303? AT&T International Calling adds discounted or unlimited rates to 200+ countries on top of your existing plan, and unlimited texting from the U.S. to 200+ destinations is already included on AT&T unlimited plans.
Where the 303 calls most:MexicoIndiaChinaVietnamCanada
Top places of birth among foreign-born residents of the 303’s counties, U.S. Census Bureau ACS 2023.
Calling abroad from a 303 number: dial 011 + country code + number (or just + on a mobile). Traveling abroad instead? International Day Pass® takes your talk, text and data with you for a flat daily rate.
International Calling and International Day Pass® availability, rates and included destinations vary by plan; see att.com for the current country list.
Denver calls the worldSee international plans ›
303 Area Code Quick Facts & Dialing
StateColorado
Time zoneMountain
Established1947original code
Dialing10 digitsrequired
Toll-free?Nogeographic code
Population3.96Mcounties served, Census 2023
Largest cityDenver+49 more ›
How to dial a 303 number
| Scenario | Format | Example |
|---|---|---|
| Local call (within the region) | 303 + 7-digit number | (303) 555-0100 |
| Long distance (within the U.S.) | 1 + 303 + 7-digit number | 1 (303) 555-0100 |
| Calling 303 from another country | +1 303 + 7-digit number | +1 303 555 0100 |
| From a mobile phone | (303) + 7-digit number | (303) 555-0100 |
A Short History of Area Code 303
One of the original area codes of 1947, the 303 has served Denver and surrounding communities from the beginning.
1947Assigned as one of the original 86 codes
1988Territory split off as 719
1995Territory split off as 970
1998First overlay: 720
2022Overlay 983 added
Area Code 303 vs the related codes
| Code | Added | Type | Where it works |
|---|---|---|---|
| 303 | 1947 | Original | Denver and surrounding communities |
| 719 | 1988 | Split | Territory carved from the 303 |
| 970 | 1995 | Split | Territory carved from the 303 |
| 720 | 1998 | Overlay | Same territory as the 303 |
| 983 | 2022 | Overlay | Same territory as the 303 |
Same rates, same local dialing: a number from any code in the region works exactly like a 303.
Nearby & Related Area Codes
Browse area codes by state: Colorado (6) · California (41) · Texas (29) · Florida (23) · all 50 states ›
Area Code 303 FAQ
What area code is 303?
303 is the area code for Denver, Colorado and the surrounding communities. It appears at the front of every local 10-digit phone number in the area.
Where is area code 303?
Area code 303 serves Denver, Colorado and nearby communities including Arvada, Aurora, Bennett. The full city list is in the cities table above.
Why did I get a text message from a 303 number?
The most common 303 text scam opens like a wrong number (“u at home?”, “are you busy tomorrow?”) and tries to move you to WhatsApp. Don’t reply. Forward the text to 7726 (SPAM) and delete it. AT&T ActiveArmor® filters known scam senders automatically.
Who called me from area code 303?
A 303 number usually means Denver or a nearby community, but spoofing is common. This page’s prefix lookup isn’t a reverse phone lookup — it can’t name the caller, but it shows the carrier, line type and community a number was issued to, which is often enough to judge a call.
What time zone is area code 303?
Mountain time. The live local time is shown at the top of this page.
Why am I getting calls from 303 numbers?
303 is an active, legitimate Colorado area code, but scammers spoof local numbers because people answer them. If there’s no voicemail, let it go. AT&T ActiveArmor® blocks and labels spam automatically, and you can report unwanted calls at reportfraud.ftc.gov. The spam report board above shows which 303 prefixes are drawing complaints right now.
Is 303 a toll-free number?
No. 303 is a geographic area code tied to Denver, Colorado. Toll-free calls come from 800, 833, 844, 855, 866, 877 and 888 numbers.
What’s the difference between 303 and 720?
720 is an overlay of 303: both cover the same Denver area, and calls between them are local. New lines may get either code.
Which cities use area code 303?
The largest communities include Arvada, Aurora, Bennett, Berthoud, Boulder. The full list is in the cities table above.
Does AT&T offer service in the 303?
Yes: home internet, wireless and retail stores across the 303. Availability is checked address by address.
Can I still get a 303 number?
Yes. Carriers in Denver and across the 303 still issue 303 numbers on new lines, and you can port an existing 303 number to any carrier. Newer lines in the same area may also receive numbers from an overlay code.
Can I keep my 303 number if I move?
Yes. Phone numbers are portable: your 303 number can move with you anywhere in the U.S., whether you stay with your carrier or switch.
Sources: city and store data from AT&T records; prefix and carrier assignments from the public numbering registry (pulled July 2026). Facts regenerate monthly.
