CSRS Annuity Calculations

The amount of the basic annuity payable upon your retirement under the Civil Service Retirement System (CSRS) is directly related to:

  • your length of creditable service and
  • your highest 3 years' average salary.

Once the basic annuity is computed, based on length of service and your earnings, it may be reduced:

  • for any service for which you did not make retirement contributions ("deposit service")
  • for service for which you have received a refund of retirement contributions ("redeposit service") and have not paid the entire redeposit due or are eligible for
  • to provide survivor benefits for your spouse or former spouse after your death
  • because you are retiring before age 55

Below are the most frequent formulas (with examples) of calculating a CSRS retirement annuity:

High-3 Average Salary: What Is It and How Is It Calculated?
Edward A. Zurndorfer, CFP
All retiring federal employees will receive an annuity that is computed based on their length of federal service and their high-three average salaries. Learn what it is, and how it's calculated. Includes helpful examples. more

High-3 Average Salary
Your "high-3" average salary is determined by finding your highest average basic pay over any three year period. The three years must be consecutive. Generally, the final three years of servic more

CSRS Basic Annuity Calculation for Regular Employees
The basic CSRS annuity is expressed as a percentage of your high-3 average salary.  Your high 3 percentage is determined by a three-part formula based on your length of creditable se more

CSRS Basic Annuity Calculation for Law Enforcement Officers and Firefighters
The basic annuity as an CSRS employee eligible to retire under the special provisions for law enforcement officers and firefighters is computed as follows: 50% of high-3 avera more

CSRS Offset Basic Annuity Calculation
The basic annuity for a CSRS Offset employee is calculated in the same as that for a regular CSRS employee: 1.5% x High-3 x first five years of service plus 1.75% x High-3 x next f more

CSRS Annuity Calculation: Early Retirement (Reduction for Age)
If you are a CSRS or CSRS Offset employee and retire before reaching age 55 due to an involuntary separation, such as in a reduction-in-force situation, your basic CSRS annuity  will&nbs more