Prefix Information
The prefix 257 is part of area code 510 serving Oakland, California.
This exchange contains 10,000 possible phone numbers (510-257-0000 through 510-257-9999).
Phone numbers with prefix 257 in area code 510. Location: Oakland, California.
The prefix 257 is part of area code 510 serving Oakland, California.
This exchange contains 10,000 possible phone numbers (510-257-0000 through 510-257-9999).