An ordinary CSRS annuity estimate becomes easier to review when each part can be traced to a pay record or a period of service. Start with the retirement system shown in your agency records and the kind of retirement your agency expects to process. The general formula is one part of that review.
A CSRS Offset estimate, a special-category calculation and a disability estimate can require additional work. A familiar job title or an online result does not settle which computation applies.
Give each part of the estimate a record
OPM describes a general formula with three service bands. The first five years use 1.5% of high-3 for each year; the next five use 1.75%; service beyond ten years uses 2%. Whole months contribute proportionately. Ask your agency to identify the credited periods behind its calculation.
| Estimate item | Record to check | Question to resolve |
|---|---|---|
| Retirement coverage | Personnel and coverage history | Is this ordinary CSRS throughout? |
| High-3 | Dated basic-pay history | Which consecutive period was used? |
| Credited service | Agency service computation | Which periods and whole months count? |
| Adjustments | Written annuity estimate | What changes the general-formula amount? |
Retain the estimate's preparation date and intended retirement date. An estimate for an earlier separation can differ because pay, service, elections or unresolved records changed.
Reconcile the complete calculation
Separate the general-formula figure from reductions, unused sick-leave credit, service-credit adjustments and deductions. An annual arithmetic amount divided by twelve is useful for comparison; it does not reproduce every step in OPM's payment calculation.
Write down what each figure represents. A gross annuity, a survivor-adjusted annuity and an expected bank deposit belong on different lines. Taxes and insurance premiums can change the amount available for household expenses without changing the service bands.
Bring focused questions to your agency
- Which record confirms my retirement coverage and retirement category?
- Does the service total include military time, refunded service or unused sick leave?
- Which open items could change this estimate before adjudication?
- How were survivor elections and recurring deductions reflected?
- Which estimate should I use when comparing different separation dates?
Keep an unresolved item visible until the responsible office answers it. A calculator cannot certify a missing service period or replace an agency determination.
Use the general CSRS formula worksheet for a local arithmetic illustration using confirmed inputs. Continue with the high-3 record check and the federal benefits review overview.
Browse federal benefits, retirement and insurance topics or read how we prepare and check our guides.
Sources
- OPM: Computation (CSRS), checked November 4, 2026
- OPM: Eligibility (CSRS), checked November 4, 2026
Have questions about your own situation? We'd be glad to help. Request a call. It's free, and there's never any obligation.