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Avalara Help Center

Does Avatax calculate using Zip + 4 or just Zip 5?


 I have a question from the head of our tax department about whether or not AvaTax utilizes full zip codes (5+4) or just the first segment.


Avalara Avatax


  • The Avatax Engine will actually use the geolocation of the street address itself if the address is a valide address within the USPS database.
    • This is what we call rooftop accuracy, as it literally drops a pin at that addressees geolocation and uses the rate of that exact pin.
  • If the address cannot be validated our system will fall back to the Zip + 4 if that was given, and if that does not check out then the Zip 5 will be used.


Note: The system will be able to calculate using only a Zip5, but we recommend at least a City/State and Zip5, incase the zip code crosses state boundaries. 





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