Prefix Information

The prefix 400 is part of area code 240 serving Germantown, Maryland.

This exchange contains 10,000 possible phone numbers (240-400-0000 through 240-400-9999).

Browse Numbers in This Prefix

240-400-0000-0999 240-400-1000-1999 240-400-2000-2999 240-400-3000-3999 240-400-4000-4999 240-400-5000-5999 240-400-6000-6999 240-400-7000-7999 240-400-8000-8999 240-400-9000-9999

Sample Numbers

(240) 400-0000 (240) 400-1234 (240) 400-2000 (240) 400-3333 (240) 400-4444 (240) 400-5555 (240) 400-6000 (240) 400-7777 (240) 400-8888 (240) 400-9999