Prefix Information
The prefix 991 is part of area code 307 serving Cheyenne, Wyoming.
This exchange contains 10,000 possible phone numbers (307-991-0000 through 307-991-9999).
Phone numbers with prefix 991 in area code 307. Location: Cheyenne, Wyoming.
The prefix 991 is part of area code 307 serving Cheyenne, Wyoming.
This exchange contains 10,000 possible phone numbers (307-991-0000 through 307-991-9999).