SST Sellers are required to use an Avalara Exemption Certificate Management System. To calculate an entity exemption, exemption certificate data must be entered into Avatax Exemptions or CertCapture prior to committing the transaction in Avatax. This can be accomplished by adding/importing certificate data into Avatax Exemptions or by using CertCapture.
SST customers are not required to use CertCapture, but the product may be beneficial given your organizational needs. If you are a CertCapture user, you will be required to ensure each certificate contains valid purchaser Ids and purchaser business types, prior to going live with SST. If the exemption certificate does not contain this data, you will need to obtain an SST exemption certificate from your exempt customer. The SST exemption certificate can be found here: SST-Exemptions