Prefix Information
The prefix 400 is part of area code 314 serving St. Louis, Missouri.
This exchange contains 10,000 possible phone numbers (314-400-0000 through 314-400-9999).
Phone numbers with prefix 400 in area code 314. Location: St. Louis, Missouri.
The prefix 400 is part of area code 314 serving St. Louis, Missouri.
This exchange contains 10,000 possible phone numbers (314-400-0000 through 314-400-9999).