Do Tennessee sellers need to replace exemption certificates that include 9 digit Tennessee account or exemption numbers with new exemption certificates that include the customers’ new 10 digit Tennessee account/exemption numbers?

No, sellers are not required to obtain new exemption certificates from customers with the new 10 digit Tennessee account/exemption numbers to replace certificates they currently have.  Either of the Tennessee account/exemption numbers may be used on a Tennessee exemption certificate to claim a sales and use tax exemption.