You want to test an Avalara AvaTax for Communications SaaS Pro (SOAP) transaction before submitting it.
Avalara AvaTax for Communications SaaS Pro (SOAP)
AvaTax for Communications has a SOAP Sandbox where you can test your transactions. Use your existing credentials to access the sandbox.
There are two endpoints for testing in the SOAP Sandbox -- one for Telecom taxes and one for Sales and Use taxes.
The sandbox is for testing purposes only. Test data cannot be used in reporting.
Data will be purged periodically by Avalara.