New York Consolidated Laws, Retirement and Social Security Law - RSS § 441. Eligibility for retirement

a. No member of a retirement system who is subject to the provisions of this article shall be eligible to retire until he has rendered a minimum of five years of credited service after July first, nineteen hundred seventy-three;  provided, however, that this limitation shall not apply to the case of a member otherwise eligible to retire for disability.  A member who attains the mandatory retirement age of the plan of which he is a member without having the requisite period of service required as a condition of eligibility for retirement, shall be separated from service upon attainment of such mandatory retirement age;  provided, however, that this requirement shall not preclude a member from being continued in service beyond such mandatory retirement age pursuant to other appropriate provisions of law.

b. Notwithstanding the provisions of subdivision a of this section, a retired member, receiving a retirement allowance for other than physical disability:  (i) who returns to active public service and joins or rejoins a public retirement system on or after July first, nineteen hundred seventy-three;  and (ii) who thereafter separates from service prior to the completion of two years of credited service, shall, upon such separation, be entitled to receive a retirement allowance which shall consist of an annuity which is the actuarial equivalent of his accumulated contributions, and the pension, including pension-providing-for-increased-take-home-pay, which he was receiving prior to his last restoration to membership.

c. Notwithstanding the provisions of subdivision a of this section, a member of a retirement system who is subject to the provisions of this article shall be eligible to retire without having rendered a minimum of five years of credited service after July first, nineteen hundred seventy-three, if such member has rendered a minimum of five years of continuous service, in the employ of the participating employer from which he retires, immediately prior to retirement.  For the purpose of this subdivision, the term “service” shall mean credited service rendered after July first, nineteen hundred seventy-three, and prior service rendered immediately before entry into a retirement system.

d. Notwithstanding the provisions of subdivision a of this section, a member of a retirement system who is subject to the provisions of this article shall be eligible to retire without having rendered a minimum of five years of credited service after July first, nineteen hundred seventy-three if such member has rendered a minimum of three years of continuous service after July first, nineteen hundred seventy-three and had rendered at least twenty years of credited service prior to January first, nineteen hundred fifty-five.