Prefix Information

The prefix 304 is part of area code 312 serving Chicago, Illinois.

This exchange contains 10,000 possible phone numbers (312-304-0000 through 312-304-9999).

Browse Numbers in This Prefix

312-304-0000-0999 312-304-1000-1999 312-304-2000-2999 312-304-3000-3999 312-304-4000-4999 312-304-5000-5999 312-304-6000-6999 312-304-7000-7999 312-304-8000-8999 312-304-9000-9999

Sample Numbers

(312) 304-0000 (312) 304-1234 (312) 304-2000 (312) 304-3333 (312) 304-4444 (312) 304-5555 (312) 304-6000 (312) 304-7777 (312) 304-8888 (312) 304-9999