Tennessee Code Title 2. Elections § 2-2-108

(a)(1) Each commission shall have an office in the county courthouse or another public building and such other locations as the commission may designate for registering voters and performing other functions required or authorized by law. The main office shall be open at least from nine o'clock a.m. (9:00 a.m.) until four o'clock p.m. (4:00 p.m.) on such day or days each week as the commission directs.

(2) In counties with administrators of elections certified under § 2-11-202(b), who receive at least ninety percent (90%) or eighty-five percent (85%) of the assessor of property's salary pursuant to § 2-12-208(a)(1) or (a)(3) [now § 2-12-208(a)], respectively, the commission office shall be open during the hours specified in this subsection (a) at least five (5) days per week. In counties with administrators certified under § 2-11-202(b), who receive at least eighty percent (80%) of the assessor of property's salary pursuant to § 2-12-208(a)(2) [now § 2-12-208(a)], the commission office shall be open during the hours specified in this subsection (a) at least four (4) days per week. The hours such offices shall be open established by this subsection (a) shall be the minimum hours, and nothing in subsection (a) shall be construed as prohibiting the election commission from requiring such offices to stay open for additional hours per day or days per week.