Tennessee Code Title 56. Insurance § 56-4-207

(a) If any employer covered by the Workers' Compensation Law, compiled in title 50, chapter 6, carries its own insurance as provided by that chapter, the employer shall pay to the commissioner four percent (4%) on the premium that the employer would be required to pay if the employer carried the full coverage insurance called for with licensed insurance companies; provided, that the tax so paid by any employer shall in no instance be less than five dollars ($5.00), and a surcharge of four tenths of one percent (0.4%) on the premium the employer would have been required to pay, the surcharge to be earmarked for the administration of the Tennessee Occupational Safety and Health Act, compiled in title 50, chapter 3. The tax shall be paid by the self-insurers to the commissioner on or before June 30 of each year. Any company or corporation electing to operate as a self-insurer and having been duly qualified as such subsequent to June 30 of any year shall pay the tax based on the estimated payroll for the balance of the year when the permit is issued; provided, that the surcharge of four tenths of one percent (0.4%) on the tax on workers' compensation insurance premiums levied by this section shall not apply to any employer who employs ten (10) or fewer employees, unless the employer is in the business of construction or manufacturing.

(b) This section shall not apply to county or municipal governments.