USPS Address Validator
Validate and format any U.S. mailing address to USPS standards. Get properly formatted addresses to ensure your mail reaches its destination.
Why Address Formatting Matters
Every year, millions of pieces of mail are returned to sender due to incorrect or improperly formatted addresses. Proper address formatting helps ensure your important mail reaches its destination on the first attempt.
USPS Standards
Get addresses formatted to official USPS specifications.
Prevent Returns
Properly formatted addresses reduce mail returns and delays.
Fast Delivery
Standardized addresses are processed faster by USPS.
Pro tip: When sending certified mail or important legal documents, always verify your address format first. This is especially important for time-sensitive mailings where a returned letter could cause missed deadlines.
Frequently Asked Questions
Why should I validate my address before mailing?
Validating your address ensures your mail reaches its destination without delays or returns. Invalid or incomplete addresses cause mail to be returned to sender, which can cost you time and money. USPS processes billions of pieces of mail annually, and proper address formatting helps ensure reliable delivery.
What does the USPS address validator check?
The validator standardizes your address to USPS format (uppercase, proper abbreviations), verifies all required fields are present, and checks that the ZIP code is valid. It prepares your address for USPS delivery standards.
What is a ZIP+4 code and why does it matter?
A ZIP+4 code is a 9-digit ZIP code (e.g., 10001-1234) that identifies a specific delivery segment like a block, building, or organization. Using ZIP+4 codes helps USPS sort and deliver mail more efficiently and reduces the chance of misdelivery.
Why was my address marked as invalid?
Common reasons include: missing required fields (street, city, state, or ZIP), typos in the address, wrong ZIP code format, or incomplete information. Try correcting any issues and ensure all required fields are filled.
How do I format an address correctly for USPS?
USPS prefers all caps, no punctuation, and a specific order: Line 1 for recipient name, Line 2 for street address (number, street name, unit), Line 3 for city, state abbreviation, and ZIP code. Example: 123 MAIN ST APT 4, ANYTOWN NY 12345-6789
More USPS Tools & Resources
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