Question 1

Where is area code 331?

Accepted Answer

Area code 331 covers Chicago and nearby cities including Naperville, Bolingbrook, Wheaton in Illinois, in the Central Time.

Question 2

What cities use area code 331?

Accepted Answer

Area code 331 serves Chicago, Naperville, Bolingbrook, Wheaton, Downers Grove, and 21 other communities in Illinois.

Question 3

What time zone is area code 331 in?

Accepted Answer

Area code 331 is in the Central Time (America/Chicago).

Question 4

How do you dial a 331 number?

Accepted Answer

Dial all 10 digits: 331 followed by the 7-digit local number. From outside the United States, dial +1 331 and the local number.

Question 5

Is a call from area code 331 a scam?

Accepted Answer

A 331 number is geographically tied to Illinois, but caller ID can be spoofed, so the displayed area code does not prove where a caller really is. If you did not expect the call, do not share personal information and consider looking the number up.

Question 6

Is 331 a country code?

Accepted Answer

No. 331 is a US area code (a domestic 3-digit code), not a country code. The country (calling) code for the United States is +1. So a full 331 number written for international dialing looks like +1 331 followed by the 7-digit local number.

Area Code 331

Cities in area code 331

Area codes by city

Other Illinois area codes

Nearby area codes