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CASS Certified Point-Of-Entry Address Validation API

Integrate real-time address correction with the CASS API

Validate and Correct Addresses in real time at Point of Entry with the AccuZIP CASS RESTful API. This address verification tool allows users to integrate address validation into their own applications, interfaces and websites. Confirm each address entered as real and deliverable by the USPS® or if an address is vacant, is a residential or business address, all in real-time to the delivery point, down to the Suite or Apartment. AccuZIP’s CASS API is CASS Certified™ by the USPS and used to clean and standardize billions of addresses each year for the last 25 years.

See if for yourself - TEST DRIVE THE CASS API NOW!


Where can I get Help with the CASS API?

The AccuZIP CASS RESTful API comes with complete documentation including all of the REST API Calls. And when you need extra help, contact our support department as often as you wish using our Live Chat service, telephone support, or through email

Professional Services

Need help integrating or customizing the CASS API? AccuZIP’s Professional Services team is there to help. This dedicated team helps simplify the complexities of programming requirements and eliminates the need to hire outside developers. Our team is dedicated to adapting to your to your needs minimizing the need to change anything in your existing workflow. We Adapt to You.

Who uses the CASS RESTful API?

  • Customer Service and Sales Reps: Integrate the CASS API into CRM platforms and Sales people can validate and correct address information on individual records prior to sending order forms, one-off correspondence and other mailed materials.
  • Marketing and Sales Reps: Marketing can pull segmented lists and validate within the CRM prior to exporting
  • Accounting: Integrate into popular accounting software platforms. Accounting can validate records prior to invoicing making for more accurate and efficient Accounts Receivable and timely receipts.
  • Online Order Fulfillment: Validate addresses on websites and online order forms ensuring accurate package deliveries while eliminating unnecessary delays and returns

Save Money and Increase your Bottomline

Watch this webinar on the High Cost of Returns that can be eliminated when implementing the CASS API saving time, money and preserving your brand image.


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