Prefix Information
The prefix 400 is part of area code 860 serving Hartford, Connecticut.
This exchange contains 10,000 possible phone numbers (860-400-0000 through 860-400-9999).
Phone numbers with prefix 400 in area code 860. Location: Hartford, Connecticut.
The prefix 400 is part of area code 860 serving Hartford, Connecticut.
This exchange contains 10,000 possible phone numbers (860-400-0000 through 860-400-9999).