Tennessee Code Title 55. Motor and Other Vehicles § 55-2-113

(a) The commissioner is authorized, but not required, to accept credit cards, debit cards or other similar financial transaction cards in payment of any taxes or fees due in connection with the titling or registration of motor vehicles, and the commissioner may adopt reasonable policies governing the manner of acceptance of such cards. The commissioner is authorized to impose a surcharge or convenience fee upon persons making payment by credit card, debit card or other similar financial transaction cards to wholly or partially offset, in the aggregate, any discount fees, administrative fees, transaction fees or other direct fees or costs charged to the department by a third party to facilitate the transaction. The commissioner may enter into appropriate agreements with card issuers or other appropriate parties as needed to facilitate the acceptance of payments authorized by this section. The commissioner also may enter into appropriate agreements with third-party service providers for the acceptance and processing of credit card, debit card or other similar financial transaction card payments on the commissioner's behalf. The agreements may authorize the third-party service provider to impose a surcharge or convenience fee upon persons making the payments. The county clerks, when acting as deputies to the commissioner under the laws governing the titling and registration of motor vehicles, are likewise authorized, but not required, to accept credit cards, debit cards or other similar financial transaction cards consistent with the authority granted to the commissioner under this section.

(b) When a person elects to make a payment by credit card, debit card or other similar financial transaction card and a surcharge or convenience fee is imposed as authorized by this section, the payment of the surcharge or convenience fee shall be deemed voluntary and shall not be refundable. No person making any payment by credit card, debit card or other similar financial transaction card shall be relieved from liability for the underlying obligation, except to the extent that the department realizes final payment of the underlying obligation in cash or the equivalent. If final payment is not made by the card issuer or other guarantor of payment, then the underlying obligation shall survive and the department shall retain all remedies for enforcement that would have applied if the transaction had not occurred.