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Why are we receiving a date error when the document date is correctly formatted?


We are receiving the following error when trying to calculate tax:

"String was not recognized as a valid DateTime."

We have our DocumentDate correctly formatted as YYYY-MM-DD.



Avalara AvaTax - SOAP API


  • If your DocumentDate is correctly formatted and you are still receiving a String was not recognized as a valid DateTime error that means that there is another Date type field in your request which is improperly formatted.

  • Please check the dates of each field that require a date field, including the deprecated PaymentDate field that is no longer used for the SOAP API.

    • Even though the PaymentDate field has been deprecated, sending non-Date information that is improperly formatted in that field will cause the error.