303 Area Code

Area code 303 is a central Colorado area code that covers Denver, Boulder and their surrounding areas. Area code 303 overlays the area code of 720.

Colorado has area codes of 303, 719, 720, 970.

Counties that Use 303 Area Code

Major Cities that Use 303 Area Code

All Cities & Towns that Use 303 Area Code

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Where is 303 area code?

The following map shows the coverage of 303 area code. The coverage area is shown in green.

Area code map of the entire U.S.