> This page is for Documentation, version Refactor guides.
> For other versions, use one of these documentation indexes:
> - Integration guides (default): https://avalara.ferndocs.com/docs/integration-guides/llms.txt
> - Refactor guides: https://avalara.ferndocs.com/docs/refactor-guides/llms.txt
> - Get certified: https://avalara.ferndocs.com/docs/get-certified/llms.txt
> - Agent to Agent (A2A): https://avalara.ferndocs.com/docs/agent-to-agent-a2a/llms.txt
> - AI use cases: https://avalara.ferndocs.com/docs/ai-use-cases/llms.txt
> - API versioning: https://avalara.ferndocs.com/docs/api-versioning/llms.txt

> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://avalara.ferndocs.com/llms.txt.
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# Error messages and response codes

Learn about AvaTax API error messages, their causes, and how to address them.

AvaTax error messages tell you what went wrong during an API call, what you can do about it, and how to proceed. These messages differ between SOAP and RESTv2.

* SOAP error codes: [https://developer.avalara.com/avatax/common-errors/](https://developer.avalara.com/avatax/common-errors/)

* RESTv2 error codes: [https://developer.avalara.com/avatax/errors/](https://developer.avalara.com/avatax/errors/)

> **Note**
>
> Part of the **SOAP To RESTV2 Refactor Guide**. [Open the full "Error messages and response codes" section on Avalara](https://developer.avalara.com/soap-to-restv2-refactor-guide/kue0600755147372/).