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US area code · Colorado

Area code 720

Where the 720 area code is, its overlay and how to dial a +1 720 number from anywhere.

CoversDenver, ColoradoTime zoneMountain (MT)TypeOverlay
Quick answer

The 720 area code is in Denver, Colorado, United States (Mountain (MT)). To call from abroad: +1 720 555-0123. It is an overlay, so all 10 digits are dialled.

StateColorado
Main areaDenver
Time zoneMountain (MT)
TypeOverlay
10-digit dialingRequired
In service since03-Mar-1998

The 720 area code is a geographic North American Numbering Plan (NANP) code covering Denver, Colorado. It has been in service since 03-Mar-1998 and sits in the Mountain (MT) time zone.

Overlay 720 shares its region

Several area codes cover the same geographic area, so two neighbours can have different codes. Because of the overlay, you must dial all 10 digits (area code + number) even for local calls.

720303983

How to dial a 720 number

From abroad+1 720 555-0123
Within the US / Canada1 720 555-0123
Locally (same area)720 555-0123

Cities in the 720 area code

A 720 number is usually in one of these places in Colorado — 12 counties.

Arvada JeffersonAurora Adams;ArapahoeBoulder BoulderBrighton Adams;WeldBroomfield Broomfield;JeffersonCastle Rock DouglasCastlewoodColumbineCommerce City AdamsDenver Adams;Arapahoe;Denver;JeffersonEnglewood ArapahoeHighlands RanchKen CarylLafayette BoulderLakewoodLittleton Arapahoe;Douglas;JeffersonLongmont Boulder;WeldLoveland LarimerNorthglennParker DouglasSouthglennThorntonWestminster AdamsWheat Ridge Jefferson

Other Colorado area codes

303719748970983

Frequently asked questions

Where is the 720 area code?

The 720 area code is in Denver, Colorado, United States (Mountain (MT)).

Is 720 an overlay area code?

Yes. 720 overlays the same region as 303, 983, so callers dial all 10 digits.

Do I have to dial 10 digits for 720?

Yes — dial the area code plus the seven-digit number.

How do I call a 720 number from another country?

Dial your exit code (or +), then 1, then 720, then the number: +1 720 555-0123.

Source: NANPA numbering plan. An area code covers a region, not a precise address — a 720 number does not pinpoint a street or ZIP code.

Missed a call from +1 720?

In the 30 days to September 24, 2026, 794 unwanted calls showing a 720 number were reported to the US Federal Trade Commission, 61% of them recorded messages or robocalls. That puts 720 at #78 of 670 area codes reported.

Other357
Reducing your debt (credit cards, mortgage, student loans)123
Dropped call or no message96
Calls pretending to be government, businesses, or family and friends55
Before you call back
  • If you do not know anyone in Colorado, do not call back: a genuine caller will leave a message or send a text.
  • Scammers fake the number shown on caller ID, so a 720 number can hide a caller anywhere in the world.
  • Never give a code received by text or a bank detail to an unknown caller. In the US, calls can be reported at reportfraud.ftc.gov.

Who issues +1 720 numbers

Phone companies hold blocks of numbers in each area code. The main holders in 720:

T-Mobile USA, Inc. 132Qwest Corporation 103New Cingular Wireless PCS, LLC 92Cellco Partnership Dba Verizon Wireless 75Bandwidth.Com CLEC, LLC 55Onvoy, LLC 54

About 37.5% of the 800 prefixes in use belong to mobile carriers: a 720 number is often a cell phone, and it may have moved to another carrier since.

Sources: FTC Do Not Call reported calls (numbers as reported by consumers, not verified), NANPA central office code assignments.

All US area codes United States +1 Map of area code 720 — cities & rate centres