Montana Title 19. Public Retirement Systems § 19-8-905. Absence due to injury or illness

(2)(a) A member absent because of an employment-related injury entitling the member to workers' compensation payments may, upon the member's return to service, contribute an amount equal to the contributions that the member would have made on the basis of the member's compensation at the commencement of the member's absence plus regular interest accruing from 1 year from the date after the member returns to service to the date the member contributes for the period of absence.

(b) Whenever a member elects to contribute under subsection (2)(a), the employer shall contribute employer contributions for the period of absence based on the salary as calculated in subsection (2)(a) and may pay interest on the employer's contribution calculated in the same manner as interest on the employee's contribution under subsection (2)(a). An employer electing to make an interest payment shall do so for all employees similarly situated. If the employer elects not to pay the interest costs, this amount must be paid by the employee.