USPS Addresses API

Plans and prices

Every plan, in full

On the record

Access requirement

From July 12, 2026, USPS says use requires a signed license agreement and tier-based fees.developers.usps.com · read 9 Oct 2026

Address validation

The Addresses API validates and corrects address information to reduce errors and improve package delivery and pricing.developers.usps.com · read 9 Oct 2026

API interface

The USPS API catalog lists REST as its API style.developers.usps.com · read 9 Oct 2026

Authentication

USPS APIs use OAuth, and users receive a Consumer Key and Secret when adding an app in the API Developer Portal.developers.usps.com · read 9 Oct 2026

Enhanced API changes

USPS says the enhanced Addresses API adds near real-time address updates, improved matching logic, and additional address indicators.developers.usps.com · read 9 Oct 2026

Intended users

The API catalog describes its APIs as tools to integrate with users’ own ideas, and the terms describe access for mailing and shipping activity and related software or services.developers.usps.com · read 9 Oct 2026

Location lookups

The API can look up valid cities and states from a ZIP Code and valid ZIP Codes from a city and state.developers.usps.com · read 9 Oct 2026

Maker history

USPS says its history began in 1775, when the Second Continental Congress appointed Benjamin Franklin postmaster general.about.usps.com · read 9 Oct 2026

Migration access

USPS states that users who did not complete onboarding lost access to the Addresses API and must start an Addresses API license signup through the Business Portal to regain access.developers.usps.com · read 9 Oct 2026

Permitted use

The general API terms limit use to USPS shipping or mailing transactions unless a specific license allows otherwise.developers.usps.com · read 9 Oct 2026

Prohibited activity

The terms prohibit using the service or its data to create address lists or databases for third-party use, and prohibit reselling the service.developers.usps.com · read 9 Oct 2026

Standardization

Address Standardization validates and standardizes domestic addresses, city and state names, and ZIP Codes to USPS addressing standards, including ZIP+4.developers.usps.com · read 9 Oct 2026

Support

USPS directs users with API issues or quota errors to submit a service request for assistance.developers.usps.com · read 9 Oct 2026

Usage limits

USPS says request limits depend on the API or data type and may be changed, and it may restrict use when it suspects data mining or address-list creation.developers.usps.com · read 9 Oct 2026

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