How ZIP Codes Are Organized by State
ZIP codes are not entirely state-specific - they're based on mail routing efficiency, not state borders. However, USPS has assigned general number ranges that tend to correspond to states. The first digit (0-9) represents a broad national region:
- 0: New England + New Jersey, Puerto Rico, Virgin Islands
- 1: New York, Pennsylvania, Delaware, Maryland, Virginia
- 2: DC, West Virginia, North and South Carolina, Georgia, Florida
- 3: Florida, Georgia, Alabama, Tennessee, Mississippi
- 4: Kentucky, Ohio, Indiana, Michigan
- 5: Iowa, Wisconsin, Minnesota, North and South Dakota, Nebraska
- 6: Missouri, Kansas, Illinois
- 7: Texas, Oklahoma, Arkansas, Louisiana
- 8: Colorado, Wyoming, New Mexico, Arizona, Utah, Nevada, Idaho
- 9: California, Oregon, Washington, Alaska, Hawaii, Pacific territories
ZIP Code Prefix by State
| State | ZIP Prefix Range | Approx. Count |
|---|---|---|
| Alabama (AL) | 35004-36925 | ~848 |
| Alaska (AK) | 99501-99950 | ~365 |
| Arizona (AZ) | 85001-86556 | ~703 |
| California (CA) | 90001-96162 | ~1,769 |
| Florida (FL) | 32004-34997 | ~1,289 |
| New York (NY) | 10001-14975 | ~1,722 |
| Texas (TX) | 73301-79999 | ~1,988 |
| Washington (WA) | 98001-99403 | ~756 |
Some states have ZIP codes that don't follow the expected prefix pattern due to historical assignments and route optimization. Always use our ZIP code lookup tool to verify specific addresses rather than relying on prefix ranges alone.
States with Most and Fewest ZIP Codes
Most ZIP codes: Texas (~1,988), California (~1,769), New York (~1,722), Pennsylvania (~1,756)
Fewest ZIP codes: Rhode Island (~67), Delaware (~80), District of Columbia (~28), Wyoming (~99)
State size doesn't always determine ZIP count - it's population density and delivery volume that matter most. Alaska is enormous but sparsely populated, so it has far fewer ZIPs than small but dense states like New Jersey.
US Territories
| Territory | ZIP Prefix |
|---|---|
| Puerto Rico (PR) | 00600-00988 |
| Virgin Islands (VI) | 00801-00805 |
| Guam (GU) | 96910-96932 |
| American Samoa (AS) | 96799 |
| Northern Mariana Islands (MP) | 96950-96952 |
How to Look Up Any State's ZIP Codes
The easiest way to browse ZIP codes by state is using our free ZIP lookup tool:
- Select your state from the dropdown on the homepage
- The tool shows all counties in that state
- Select a county to see all cities
- Select a city to see all ZIP codes, with maps and demographic data
FAQ
Q: Can a ZIP code cross state lines?
A: Yes, a small number of ZIP codes cross state boundaries where it's more efficient for mail routing. This is rare but it happens - particularly in border areas.
Q: How do I find all ZIP codes for a specific city?
A: Large cities have multiple ZIP codes. Use our lookup tool - select state, then county, then city to see all ZIP codes for that city.