Colorado · Mountain Time Updated July 2026

Area Codes in Colorado

10 codes, from a 1947 original to 2022’s newest, and an 11th on the way

Colorado has 5 active area codes — from 303 in 1947 to 983 in 2022. Three serve metro Denver (303, 720, 983); 719 is Pueblo and its surroundings; 970 is Fort Collins and its surroundings. Tap any code below for its full guide: who called, cities and ZIP codes, the coverage map and the live local time.

Not sure which code is yours? Every Colorado city is covered below. Find your city ›
Area codes5
Original303 · 1947
Newest983 · 2022
Largest metroColorado Springs
Local time11:30 PM MT
Who called me?

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Cities & ZIP codes

Every city in the 404, with ZIPs and internet type.

Coverage map

Exactly where area code 404 reaches.

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Home internet

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All 5 Colorado Area Codes

Every active code: tap any card for its full guide, who called, cities and ZIPs, map, spam patterns and local time.

Got a call from a Colorado number you don’t recognize? Open that code’s guide above for its full prefix lookup. AT&T ActiveArmor® blocks spam automatically, 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 how ActiveArmor works

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.

CityArea code(s)
Denver303 720 983
Aurora303 720 983
Lakewood303 720 983
Lone Tree303 983
Westminster303 720 983
Broomfield303 983
Castle Rock303 983
Fort Collins970
Grand Junction970
Parker303 983
Pueblo719
Alamosa719
Aspen970
Avon970
Boulder303 720 983
Brighton303 720 983
Cortez970
Dillon970

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 serviceCodeHow it arrived
1947303One of the original area codes of 1947
1988719Split from 303
1995970Added to the 303 region
1998720Added to the 303 region
2022983Added 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. Tap any code above for its detailed coverage map.

Map of Colorado area codes with anchor cities↓  Printable PDF

Open the printable Colorado area code map (PDF) — poster format with a QR code back to this page.

AT&T IN GEORGIA

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.

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.

Start with home internet in Colorado, or pair it with wireless in an internet + wireless bundle.

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Home internet across ColoradoCheck your address ›

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.

5G across ColoradoActiveArmor® includedKeep your 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.

See the AT&T wireless coverage map for Colorado ›

Woman smiling at her phone on a downtown street
Stay connected across ColoradoShop wireless plans ›

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

AT&T store employee helping a customer with her phone
Real help from real people across ColoradoFind a store ›

Area Codes in Neighboring States

Colorado Area Code FAQ

How many area codes does Colorado have?
Colorado has 5 active area codes: 303, 719, 720, 970, 983. Each links to a full guide above.
Which Colorado area code is mine?
Tap any code above to see the communities it serves; each guide lists cities with ZIP codes and a coverage map.
Who called me from a Colorado number?
Open that code's guide and check the prefix lookup: every assigned prefix with its carrier. No voicemail? Let it go — legitimate callers leave messages.
What time zone is Colorado in?
Colorado is primarily on Mountain time. The live local time is shown at the top of this page.
Does AT&T offer service in Colorado?
Yes — home internet, wireless and retail stores across Colorado. Availability is checked address by address.
Sources: prefix and carrier assignments from the NANPA central-office code registry; population figures from the U.S. Census Bureau; spam-pattern indicators from FTC Do Not Call filings and AT&T ActiveArmor® network telemetry. Facts are rebuilt from these sources at build time; the page regenerates monthly.
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