A vested member of the Public Employees' Retirement System of Mississippi (PERS), whether active or inactive, may purchase eligible service at actuarial cost, provided the member has entered or reentered state service after completion of the service to be purchased. A member is vested if he or she has the required number of years of membership service to receive a service retirement allowance at age 60.
27 Miss. Code. R. 210-64-101