All 6 Colorado area codes
Every active code: tap any card for its full guide, who called, cities and ZIPs, map, spam patterns and local time.
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Why metro Denver has 3 area codes
When a region uses more numbers than one code can hold, new codes are overlaid on the same territory rather than forcing anyone to change numbers. Metro Denver now uses 303, 720 and 983: same neighborhoods, ten-digit dialing, and every one of them covered by its own guide above.
Colorado area codes by city
The largest Colorado communities and the area codes that serve them. Every city links to its local AT&T internet page.
How Colorado got its codes
Every Colorado area code, in the order it entered service. Splits carved new regions; added codes overlay existing ones, which is why ten-digit dialing is standard.
| In service | Code | How it arrived |
|---|---|---|
| 1947 | 303 | One of the original area codes of 1947 |
| 1988 | 719 | Split from 303 |
| 1995 | 970 | Added to the 303 region |
| 1998 | 720 | Added to the 303 region |
| 2022 | 983 | Added to the 303 region |
Source: NANPA NPA database, July 2026. Regenerated monthly.
Colorado area code map
Every active Colorado area code at a glance, anchored to the metro each one serves. Click or tap any region on the map to open that code’s full guide.
How Colorado’s codes work
How Colorado splits
Denver runs on 303, 720 and 983, Colorado Springs on 719, and Fort Collins on 970.
Overlays share one territory
An overlay serves the exact same area as the code it joins: new numbers, same map. Denver carries three (303, 720 and 983).
Reading the map
Each color is one code territory. The chip shows the main code with its overlays beneath it, and clicking any region opens that code’s full guide.
Every code links to a full guide.
Who called, cities and ZIPs, maps and spam patterns.
Take the map with youPoster format with every Colorado area code, its overlays, and a QR code back to this page.↓ Download the printable PDF
Internet, wireless & stores across the state
AT&T home internet in Colorado
AT&T home internet is available across Colorado, checked address by address; every area code guide above lists its cities and what’s offered there.
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.
Start with home internet in Colorado, or pair it with wireless in an internet + wireless bundle.
AT&T wireless in Colorado
AT&T’s 5G network covers most of Colorado. ActiveArmor® spam blocking is included with every unlimited plan, your number stays yours when you move between Colorado codes, and great cell phone deals in Colorado are a tap away.
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.
AT&T stores across Colorado
From the Colorado Springs metro to Lone Tree, Denver and beyond, walk in for switching, porting, upgrades and hands-on help. Every area code guide lists its nearest stores.
Find stores in: Colorado Springs · Lone Tree · Denver · Lakewood · Aurora
