Tennessee Code Title 67. Taxes and Licenses § 67-1-114

(a) With respect to taxes imposed under chapter 2 of this title, under chapter 4, part 20 or 21 of this title, or under chapter 8, part 1 of this title, whenever the due date for filing the return occurs on a legal holiday as defined under 26 U.S.C. § 7503, the commissioner is authorized, in the commissioner's discretion, to extend the due date of such return to the next succeeding day that is not a Saturday, Sunday or legal holiday.

(b) With respect to taxes administered and collected by the commissioner of revenue, whenever the internal revenue service generally extends for all taxpayers the due date of a federal return or extends the due date of such return for a specified group of taxpayers such as, but not limited to, those affected by a federally declared disaster, the commissioner of revenue is authorized, in the commissioner's discretion, to extend the due date for the filing of specified returns to a date that shall not be later than the last day of the extension period specified by the internal revenue service.

(c) For purposes of this section, “return” shall be deemed to include any remittance or other tax document, including, but not limited to, quarterly estimated payments and extension requests.