Apply the regular FERS age-and-service factor for 2026
For the ordinary formula, multiply high-3 by full years and months of creditable service and the applicable factor. The factor is generally 1%. It becomes 1.1% only when the employee is at least age 62 at separation and has at least 20 years of service. Both conditions matter; using the enhanced factor because one threshold is met overstates the basic annuity.
Convert months to twelfths without treating leftover days as another month. The gross annual estimate divided by twelve supplies a monthly view. This branch does not cover special-category enhanced service, disability retirement, phased retirement, a CSRS component, or reserve technician complexities. The 2026 label describes the review context, not a promise that a formula input or retirement date has been approved.
A TSP-like accumulation scenario can be explored in the 401(k) projection module without adding its result to FERS until account balances and timing are independently verified.
Reserve final FERS determinations for OPM and personnel records
Eligibility categories, minimum retirement age, discontinued service, disability, special employees, deposit service, and court orders are legal and administrative questions. The calculator cannot examine an SF-50, OPF, retirement coverage code, or survivor documentation. It should not be used to select a retirement date without current agency and OPM review.
Retain the high-3 worksheet, service chronology, factor test, and source date with the estimate. Ask the agency benefits office to resolve missing or conflicting records before separation. This page offers educational arithmetic only and is not an official OPM computation, employment recommendation, tax projection, investment plan, benefits eligibility decision, or legal opinion.
Construct the FERS high-3 from actual basic-pay periods
High-3 is the highest average basic pay over three consecutive years, weighted for the time each rate was in effect. It is not automatically the last three calendar-year W-2 totals and generally excludes overtime and bonuses. Promotions, locality pay that is basic pay for retirement, part-time tours, leave without pay, and separated service periods require official personnel records rather than a guessed final salary.
Record the effective date and retirement-covered basic-pay rate for every segment in the candidate high-3 window. The calculator accepts a declared high-3, so the user remains responsible for reconstructing or confirming it. OPM recommends checking the Official Personnel Folder for service dates, pay changes, tours of duty, and military service documentation. A dollar entered without that evidence is a scenario, not a certified average.
If an IRA owner also has a 2026 minimum distribution, calculate that separate statutory floor with the 2026 RMD calculator, because the FERS basic annuity formula does not derive an IRA distribution.
Separate the FERS basic formula from award reductions and additions
The calculated amount is before survivor-election reductions, age reductions, unpaid deposits or redeposits, court orders, insurance premiums, taxes, and other deductions. It also excludes the annuity supplement, TSP withdrawals, and Social Security. Unused sick leave, military deposits, part-time service, and special retirement coverage can change computation details and must be verified under OPM rules.
A useful audit compares the gross estimate with the agency retirement estimate line by line. Differences should be traced to high-3 periods, service credit, factor branch, survivor election, and reductions rather than absorbed into an unexplained adjustment. The screen does not calculate the 2026 FERS COLA entitlement; OPM states that most regular FERS retirees begin COLA eligibility at age 62 under rules with exceptions.
For a portfolio-withdrawal gap after the pension estimate is documented, use the retirement drawdown calculator and label the FERS amount as a gross, user-entered benefit assumption.