FERS creditable service can include:
(for more specific details, see the related articles listed below)

- generally the period of time from each date of appointment to date of separation (when deductions were paid into the retirement system)

- Leave without pay (LWOP) if it does not exceed six months within a calendar year

- Part-time service

- Intermittent service (time actually served, WAE [when-actually-employed]) - up to 260 days a year.

- workers compensation is creditable if the employee returns to duty

- breaks in service of up to 3 days

- Deposit service  (time employee worked for federal government but there were no dedeductions for FERS retirement, if performed before January 1, 1989). 

- Military service

- Unused sick leave  (only used to extend length of service for FERS employees who transferred from CSRS and have a CSRS component to their retirement annuity).

Related Articles & Resources

·  FERS Refund of Employee Retirement Contributions ·  What Is a Deposit and When Is It Required? FERS and "Trans" FERS ·  FERS Sick Leave Credit ·  FERS: Military Service Credit (Military Service "Buy-Back") ·  FERS Redeposit Service (Refunded Service) ·  FERS Deposit Service (Non-Deduction Service) ·  FERS Part-Time Service Credit