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Details of 52577 Zip Code



Detail Info for 52577 Zip Code U.S Zip Info
Zip Code : 52577
Type : STANDARD
City : Oskaloosa
State : IA
County : Mahaska County
Acceptable Cities: Keomah Village, Keomah Vlg
UnAcceptable Cities: Evans, Wright
Time Zone : America/Chicago
Area Codes : 641
Latitute : 41,29
Longitude : -92,63
 US ZIP Codes are 5-digit postal codes introduced in 1963 by the USPS to improve mail sorting efficiency. The first digit represents a region (0-9), the next two signify a sectional center facility, and the last two pinpoint a local post office. A 4-digit extension ("+4") is often used for specific delivery routes.
Key Details About US ZIP Codes
Structure: 5 digits (e.g., 90210) or ZIP+4 (e.g., 90210-1234).
Purpose: The Zone Improvement Plan (ZIP) system allows the USPS to automatically route mail more efficiently.
Geographic Breakdown:
1st Digit: Represents a group of states (e.g., 0=Northeast, 9=West).
2nd/3rd Digits: Represent a regional area or large city.
4th/5th Digits: Identify specific post offices or delivery areas.
Ranges by State: For example, California is 900-961, while New York is 005 and 100-149.
Usage: They are essential for accurate mail delivery, navigation, and location-based services.

Map of 52577

ZIP codes are a system of postal codes used by the United States Postal Service (USPS) since 1963. The term ZIP, an acronym for Zone Improvement Plan, is properly written in capital letters and was chosen to suggest that the mail travels more efficiently, and therefore more quickly, when senders use the code in the postal address. The basic format consists of five decimal numerical digits. An extended ZIP+4 code, introduced in the 1980s, includes the five digits of the ZIP code, a hyphen, and four more digits that determine a more precise location than the ZIP code alone. The term ZIP code was originally registered as a servicemark (a type of trademark) by the U.S. Postal Service, but its registration has since expired.

ZIP codes designate only delivery points within the United States and its dependencies, as well as locations of its armed forces. There are no ZIP codes reserved for designating mail bound for foreign destinations (with the exception of U.S. military units stationed outside of the United States), and therefore, international outbound mail should not include a ZIP code in the delivery address. The last line of a foreign address must only show the name of the country of destination.

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