Need to look up a ZIP Code™? Try the ZIP Code™ lookup tool on USPS.com. Note: The ZIP Code™ lookup tool will display the address in USPS standardized format. This may look different than the …

The ZIP Code system (an acronym for Zone Improvement Plan[1]) is the system of postal codes used by the United States Postal Service (USPS). The term ZIP was chosen to suggest that the mail travels …

Jun 11, 2025 · What is a ZIP Code? A ZIP Code is a smart system that keeps America’s mail moving efficiently. It was created by the United States Postal Service (USPS) in 1963. ZIP stands for Zone …

At its core, a ZIP code is a U.S. postal code that lets the United States Postal Service group addresses into logical clusters so machines and people can sort mail and deliver mail reliably. A standard five …

Oct 21, 2025 · ZIP Code, system of zone coding (postal coding) introduced by the U.S. Post Office Department (now the U.S. Postal Service) in 1963 to facilitate the sorting and delivery of mail.

Jan 9, 2025 · Zip codes, or Zone Improvement Plans, are numerical codes assigned by the United States Postal Service (USPS) to facilitate the efficient delivery of mail. Introduced in 1963, these five …

As the name suggests, the US ZIP code list lists ZIP codes of all the addresses inside the United States. The USPS maintains the US ZIP codes list because it is the official postal authority of the United States.

Jul 30, 2024 · What is a ZIP Code in the US? In the US, ZIP Code stands for “Zone Improvement Plan Code,” a postal code system introduced by USPS to efficiently organize mail delivery by dividing …

Jun 21, 2025 · ZIP codes are structured to provide a systematic way of identifying geographic locations for efficient mail delivery. The standard ZIP code consists of five digits, while an extended version, …

Jan 25, 2025 · Learn how to find the correct ZIP Code using USPS tools, understand ZIP+4 codes, avoid common mistakes, and prevent mail delays or returns.