Before taking office, the Tennessee Constitution, Article X, Section 1, provides that every person chosen to any office of trust must take an oath to "support the Constitution of this state and of the United States, and an oath of office." Review Oaths of Office for examples of different oaths.

There are various statutes throughout the Tennessee code providing for administering oaths to particular officials.  There is also a general provision found at T.C.A. § 8-18-109(b), which provides that oaths of office for any elected or appointed official may be administered by the county mayor, the county clerk, a judge (current or retired) of any court of record in the county, or a current or retired judge of the general sessions court.  In addition, under § T.C.A. 8-18-107, the governor, an active or retired supreme court justice, an active or retired inferior court judge, or an active or retired general sessions judge may administer the oath of office to an inferior court judge and, except as otherwise provided by law, to any other elected or appointed official. Notaries public are authorized to administer oaths pursuant to T.C.A. § 8-16-112. Members of the general assembly are also authorized to administer oaths to county officials. T.C.A.. § 3-1-105. The oath of office for any county official required to file an oath may be administered at any time after the certification of the election returns by the appropriate legal authority in the case of elected officials, or after appointment in the case of appointed officials. However, even if the official files an oath before the scheduled start of a term of office, the official may not take office until the term officially begins. T.C.A. § 8-18-109.

The oath must be written and subscribed by the person taking it. Accompanying the oath must be a certificate executed by the officer administering the oath specifying the day and the year it was taken. T.C.A. § 8-18-107. The oath and the certificate are filed in the office of the county clerk, who endorses on them the day and year of filing, and signs the endorsement. T.C.A. §§ 8-18-109, 8-18-110. Any county official who fails to take and file the required oaths is guilty of a misdemeanor. T.C.A. § 8-18-113.