United States Phone Number Format Guide
Quick Overview
US phone numbers follow the North American format: 10 digits (XXX-XXX-XXXX) with country code +1.
United States Phone Number Generator
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Try United States Phone Number GeneratorUnited States Phone Number Format Structure
US phone numbers follow a standardized format with several components:
Components
- Country Code: +1 (optional)
- Area Code: 3 digits (XXX)
- Central Office Code: 3 digits (XXX)
- Line Number: 4 digits (XXXX)
Format Examples
+1 (555) 123-4567- Full format with country code(555) 123-4567- Domestic format555-123-4567- Simple format5551234567- Plain format
United States Phone Number Area Code Distribution
Area codes in the United States are geographically assigned:
Major Regions
- 201-299: Northeast Region
- 300-399: Southeast Region
- 400-499: Southeast Region
- 500-599: Central Region
- 600-699: Central Region
- 700-799: Western Region
- 800-899: Toll-free numbers
- 900-999: Premium rate numbers
Major Cities
- 212, 646, 917: New York City
- 213, 310, 323: Los Angeles
- 312: Chicago
- 415, 628: San Francisco
- 202: Washington DC
- 305, 786: Miami
United States Phone Number Rules and Restrictions
Area Code Rules
Cannot start with 0 or 1
Cannot have 9 as second digit when first digit is 3-7
Second and third digits cannot both be 1
Special Considerations
- 555-0100 through 555-0199 are reserved for fictional use
- Numbers beginning with 911, 411, etc. are reserved for emergency/special services
- Some area codes are reserved for future use
United States Phone Number Recent Changes
- New area codes are regularly added due to number exhaustion
- Some regions now require 10-digit dialing for all calls
- Overlay area codes are becoming more common in populous areas