Estimate your time to retire under FERS

Note: This is the day you started working for the federal government for retirement purposes, or your service computation date. If you don’t know it try to estimate as best you can.
To get it, start with the date of your first day on the job and adjust the date forward for any breaks in service.
Temporary service only counts prior to 1989, and only if a deposit is made for that.

If you took out your retirement contributions on a break in service you won’t get credit for that service time unless you have paid a deposit to get recredited for that time. To get credit for any working time for which no you made no retirement contributions in the first place, you must make a deposit.

Adjust the date back for any active duty military service you have paid a deposit for or plan to pay one for. Remember, if you are eligible for active military retired pay, in general you would have to waive it in order to apply your military time toward a federal retirement annuity.