Colorado Area Codes
Compare 6 in-service area codes assigned to Colorado. Explore each code’s introduction date, overlays, possible time zones, and public prefix records.
Colorado numbering at a glance
- In-service area codes
- 6
- Time-zone labels in NANPA data
- Mountain
- Listed in-service or assigned prefixes
- 3,044 · source dated 2026-09-29
These are numbering assignments. The counts do not represent active phone numbers, current carriers, or a caller’s physical location.
Compare area codes in Colorado
| Code | Introduced | Other codes in overlay | Time zones | Listed prefixes |
|---|---|---|---|---|
| 303 | 01-Jan-1947 | 720, 983 | Mountain | 784 |
| 719 | 05-Mar-1988 | None listed | Mountain | 663 |
| 720 | 01-Jun-1998 | 303, 983 | Mountain | 785 |
| 748 | 07-Jul-2025 | 970 | Mountain | — |
| 970 | 02-Apr-1995 | 748 | Mountain | 770 |
| 983 | 17-Jun-2022 | 303, 720 | Mountain | 42 |
Source: NANPA NPA database, dated 2026-09-28. Prefix counts: NANPA US assignment report. View official area-code maps.
Overlay groups in Colorado
Codes in an overlay group can serve the same broad numbering area. A person may keep a number after moving, and the displayed number may be spoofed.
Find a number in Colorado
Open an area-code page above to check a prefix and possible time zones. You can also search US telephone rate-center names; those names are not exact city coverage.
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