U.S. postal lookup

U.S. ZIP Codes Database 2026

Search by ZIP code, city, county, or state and find clear postal details with maps, time zones, and area code data.

42,735 verified records

All states and U.S. territories

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State directory

Illinois ZIP Codes

Complete postal directory, details, and geographic map for the State of Illinois.

State	ZIP Code	City	County	Area Codes
IL	61462	Monmouth	Warren County	`309`
IL	61465	New Windsor	Mercer County	`309`
IL	61466	North Henderson	Mercer County	`309`
IL	61467	Oneida	Knox County	`309`
IL	61468	Ophiem	Henry County	`309`
IL	61469	Oquawka	Henderson County	`309, 319`
IL	61470	Prairie City	McDonough County	`309`
IL	61471	Raritan	Henderson County	`309`
IL	61472	Rio	Knox County	`309`
IL	61473	Roseville	Warren County	`309`

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About U.S. ZIP Codes

ZIP codes are a United States Postal Service system introduced in 1963 to make mail routing more accurate and efficient. The standard format uses five digits, while ZIP+4 adds four more digits for a more precise delivery segment.

ZIP codes cover the United States, its territories, military mail routes, and other USPS delivery points. This directory organizes that data for practical lookup by ZIP code, city, county, and state.