Prefix Information

The prefix 340 is part of area code 312 serving Chicago, Illinois.

This exchange contains 10,000 possible phone numbers (312-340-0000 through 312-340-9999).

Browse Numbers in This Prefix

312-340-0000-0999 312-340-1000-1999 312-340-2000-2999 312-340-3000-3999 312-340-4000-4999 312-340-5000-5999 312-340-6000-6999 312-340-7000-7999 312-340-8000-8999 312-340-9000-9999

Sample Numbers

(312) 340-0000 (312) 340-1234 (312) 340-2000 (312) 340-3333 (312) 340-4444 (312) 340-5555 (312) 340-6000 (312) 340-7777 (312) 340-8888 (312) 340-9999