Federal Employees Retirement System (FERS) - Benefits.gov
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5% service, do not surpass 10 years, 2% of your high-3 average income multiplied by your years of other service in excess of 10 years Reductions in Non-Disability Annuity Age If you retire under the MRA +10 arrangement If you have 10 or more years of service and retire at the Minimum Retirement Age (MRA), your benefit will be minimized by 5/12 of 1% for each full month (5% each year) that you were under age 62 on the date your annuity started.
If you delay the start date of your annuity, the age reduction will be reduced or gotten rid of. The age decrease applies to both the Civil Service Retirement System and the Federal Worker Retirement System elements of your annuity, if you transferred to FERS and part of your annuity is calculated under the CSRS arrangement.

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The reduction is 1/6 of 1% (2% each year) for every single month that you are under age 55 at the time of retirement. Survivor Benefits If you are married, your advantage will be minimized for a survivor advantage, unless your spouse granted your election of less than a full survivor annuity.
If the overall equals 25%, the reduction is 5%. Learn More Here or Refunded Service If you have a CSRS part in your annuity: The CSRS portion of your advantage will be lowered by 10% of any deposit owed for CSRS non-deduction service performed before October 1, 1982, unless the deposit was paid prior to retirement.
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Alternative Annuity Your benefit may be reduced if you elected a swelling sum payment equivalent to your retirement contributions and a minimized regular monthly annuity, frequently called an alternative annuity. Just non-disability annuitants who have a dangerous affliction or other crucial medical condition can choose this choice. Disability Retirement Calculation FERS impairment advantages are computed in various methods depending upon the annuitant's age and amount of service at retirement.