The following is a list of all the types of service that NYCERS recognizes. Please note, however, that not all plans allow all these types of service to be counted toward retirement. Many special occupation plans have stricter requirements and might not allow previous service from a different profession to be counted toward retirement.

• Membership Service:  This is defined as paid full-time or part-time service performed after you last joined NYCERS, including all service while you are on the payroll of a participating employer, certain military service, and membership reinstatement.
• Transferred Service:  Service that was credited to you while you were a member of another public retirement system in the City or State of New York which you transferred to NYCERS.
• Purchased Service (Buy-Back):  Service credit purchased for full- or part-time public service performed before becoming a member of the pension system. Buying back service credit does not change your membership date.
• Membership/Tier Reinstatement: Current members who were previous members of a public employee retirement system in New York City or New York State may apply to restore their original membership date. In order to be eligible, the first membership must have been terminated. Unlike purchasing previous service, membership reinstatement requires that you were previously a member of a public employee retirement system, not merely employed by a public entity that would have allowed you to join a retirement system.
  A key benefit of membership reinstatement is reinstating to an earlier tier. If your first membership date was between July 27, 1976, and March 31, 2012, you could reinstate to Tier 4. If your first membership date was on or after July 1, 1973 and prior to July 27, 1976, you could reinstate to Tier 2. The benefits in Tiers 4 and 2 are generally better than those in Tier 6, so if you think you might be eligible you should consider applying. In order to make an informed decision, please visit our Customer Service Center and speak to a representative. In most cases the benefits will outweigh any cost, but individual cases differ.
• Military Service: Service credited for time spent on duty in one of the military branches of the U.S. Armed Forces. There are various laws that allow members to purchase Military service and each law has different provisions. You are entitled to receive credit for Military service under whatever law provides you with the greatest benefit.
• Union Leave Service:  Credited service granted for an authorized leave of absence without pay to conduct labor relations activity on behalf of a public employee union.
• Part-time Service:  Part-time service is service in which an employee is regularly scheduled to work less than 1,827 hours in a calendar year. Part-time service can be Membership Service, Purchased Service, Transferred Service, etc. Regardless of how part-time service is obtained, NYCERS will prorate credit on the basis of one year of full-time service — 1,827 hours worked in a calendar year.