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AMS API is software used to develop address matching software. This software provides access to USPS® matching logic, which allows users to verify the accuracy of ZIP + 4® returns. AMS API may be integrated within a manufacturers’ product and redistributed by the manufacturer.

The DPV®, LACSLink®, RDI and eLOT® files can be used in conjunction with the AMS API Developer's Kit.

AMS API contains the following information:

  • API library(s) for each specific computer platform
  • Interface definition file (ZIP4.H)
  • Test utility (SAMPLE.EXE)
  • Test utility source code
  • Sample configuration data files
  • User documentation

The test utility can be used to ensure the Address Matching System and data files have been installed correctly and to provide access to USPS matching logic, which displays the standardized address returned by the matching engine. Additionally the AMS software, including but not limited to, .DLLs, shared objects and static objects, all expire and cease functionality based on the CASS guidelines.

CASS certification is not a requirement for the AMS API Product. However to receive automation discounts, users must obtain CASS certification.

The AMS API Product is updated bimonthly, unless requested monthly, via CD.

Annual License Fee: Pricing varies depending on the product(s) and platform(s) used.

What’s next?
The AMS API License Agreement requires signature compliance and subscriptions are maintained on a calendar year basis. The RDI Product requires a direct license from the USPS. To obtain order forms or for more information, call the National Customer Support Center at 877-640-0724.

Contact Information:

  • Phone: 877-640-0724
  • Email: AMSAPI@usps.gov
  • Page updated: 4/26/2011

Important Updates

Standard Mail DSCF Load Leveling Final Rule Published in the Federal Register

The Postal Service has released its Federal Register final rule revising the service standards for Standard Mail that is eligible for Destination Sectional Center Facility (DSCF) rates. These changes will allow a more balanced distribution of DSCF Standard Mail across delivery days. With its new rules, USPS is extending delivery expectation to four days for mail entered on Friday and Saturday. National Implementation began April 10, 2014.

January 2014 Price Change Fact Sheets

Getting Started with Full-Service Intelligent Mail

PostalOne! Contingency Plan

For mailers unable to submit electronic information, click here for the PostalOne! Contingency Plan.


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