S.C. Code Ann. § 9-1-1515

(A) In addition to other types of retirement provided by this chapter, a Class One or Class Two member may elect early retirement if the member: (1) has five or more years of earned service; (2) has attained the age of fifty-five years; (3) has at least twenty-five years of creditable service; and (4) has separated from service. A member electing early retirement shall apply in the manner provided in Section 9-1-1510. (B) The benefits for a member electing early retirement under this section must be calculated in the manner provided in Section 9-1-1550, except that in lieu of any other reduction factor, the member's early retirement allowance is reduced by four percent a year, prorated for periods less than one year, for each year of creditable service less than twenty-eight. (C) A member who elects early retirement under this section is ineligible to receive any cost-of-living increase provided by law to retirees until the second July first after the date the member attains age sixty; or the second July first after the date the member would have twenty-eight years' creditable service had he not retired, whichever is earlier. (D)(1) Except as provided in item (2) of this subsection, a member who elects early retirement under this section is not covered by the State Insurance Benefits Plan until the earlier of: (a) the date the member attains age sixty, or (b) the date the member would have twenty-eight years' creditable service had he not retired. (2) A member taking early retirement may maintain coverage under the State Insurance Benefits Plan until the date his coverage is reinstated pursuant to item (1) of this subsection by paying the total premium cost, including the employer's contribution, in the manner provided by the Division of Insurance Services of the board.