Prefix Information
The prefix 640 is part of area code 628 serving San Francisco, California.
This exchange contains 10,000 possible phone numbers (628-640-0000 through 628-640-9999).
Phone numbers with prefix 640 in area code 628. Location: San Francisco, California.
The prefix 640 is part of area code 628 serving San Francisco, California.
This exchange contains 10,000 possible phone numbers (628-640-0000 through 628-640-9999).