40 ILCS 5/18-112.1

Payment by this system to the General Assembly Retirement System shall be made at the same time as the transfer of credits and shall consist of: (1) the amounts credited to the applicant, through employee contributions, including interest if applicable, on the date of transfer; and (2) employer contributions equal to the accumulated employee contributions as determined under clause (1) above. Participation in this system shall terminate on the date of transfer. (b) An active member of the General Assembly may reinstate service credits terminated upon receipt of a refund by repaying to the system the amount of the refund together with interest thereon, to the date of payment.