N.Y.C. Admin. Code § 13-119: § 13-119 Re-entry into membership after withdrawal of contributions.

If a member has received benefits under section 13-141 of this chapter, such member's prior-service credit and member-service credit at the time of leaving service shall be restored in full provided such member return to service within five years after leaving service and redeposits the total amount so withdrawn. Subsequent contributions will be at the rate applicable to his or her age on re-entry to service.