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SCD calculator

Service computation date calculator

This service computation date calculator turns up to six periods of service into the dates the government uses: your retirement SCD, your leave SCD and your TSP SCD. It counts time on OPM's 360-day year, credits military service the way each date allows, subtracts excess leave without pay, and shows your leave accrual tier and agency 1 percent vesting date.

The calculator

What the calculator shows

  • Your total creditable service in years, months and days, counted the way OPM counts it.
  • Your retirement SCD, with military service included only where the deposit is paid.
  • Your leave SCD, with all honorable military service included, the date in block 31 of your SF-50.
  • Your annual leave accrual tier, 4, 6 or 8 hours a pay period, and how far you are from the next one.
  • Your TSP SCD and agency 1 percent vesting date, three years after your earliest civilian start.
  • Excess leave without pay subtracted from both the retirement and leave dates, and shown as its own line.

Your inputs

One row per period. Military rows count toward the leave date always, and toward the retirement date only when the deposit is paid. Add a row for any calendar year with more than 6 months of leave without pay.

Prefilled with an example so the result is never empty. Change any number; the result updates as you type.

Educational estimate on the assumptions you entered

March 1, 2005

your retirement service computation date on these rows, 21 years, 7 months, 12 days of creditable service

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Retirement SCD
March 1, 2005: 21 years, 7 months, 12 days
Leave SCD
March 1, 2005: 21 years, 7 months, 12 days
Leave accrual
8 hours of annual leave a pay period
TSP SCD
March 2, 2009; vested in the agency 1% on March 2, 2012
Leave without pay
None entered
Day count
OPM's 360-day year, 30 days to a month; odd days drop at retirement

Assumptions behind this estimate

  • Dates are what you type. The calculator does not check them against your SF-50s, DD 214 or SF-144A.
  • Each period counts its last day, and every month is 30 days, as OPM's worksheet does. A 31st counts as the 30th.
  • Military rows are honorable active duty. Military retirees get leave credit only for service during a war declared by Congress or a campaign with a badge, or for all active duty when retirement resulted from a disability caused by armed conflict (OPM, retrieved 2026-10-13); check with HR before relying on the leave date.
  • Leave without pay rows hold only the excess past 6 months in a calendar year. The calculator subtracts the whole row from both dates.
  • The TSP SCD is your earliest civilian start. Breaks in civilian service can make the agency's TSP SCD and vesting date later than shown.
  • Accrual tiers are full-time rates. Senior Executive Service and similar positions accrue 8 hours a pay period regardless of service (OPM, retrieved 2026-10-13).
  • No deposit or refund rules for civilian service are modeled. Civilian time is counted as creditable as entered.

Educational estimate on the assumptions you entered, not a projection or a promise and not OPM's official computation. FFEBA is an education organization, not a financial advisor, and does not give personalized financial, tax or legal advice.

Inputs you will enter

  • Service periodsUp to six rows, one for each stretch of service. A new row starts at each break in service, each change between civilian and military, and each block of leave without pay that counts against you.
  • FromThe first day of the period, from the SF-50 that started it or your DD 214 for military service.
  • ToThe last day of the period. For your current job, use today's date.
  • Counts asCivilian service; Military, deposit paid; Military, no deposit; or Leave without pay over 6 months. For the last choice, enter only the stretch beyond the first 6 months of nonpay in that calendar year.
  • Compute as ofThe date the SCDs count back from. It starts at today; move it to a planned retirement day to see your dates then.

How we compute it

We count each period from its first day through its last, giving a day's credit for each day from appointment through separation, as OPM does (OPM, retrieved 2026-10-13). Time is counted on a 360-day year with 30 days to a month, the convention in OPM's own SCD worksheet, where every month is treated as 30 days when borrowing (OPM, retrieved 2026-10-13). We add the periods that count for each date, subtract any excess leave without pay, and count that total back from the compute-as-of date.

The retirement SCD adds civilian service and military service with the deposit paid. Under FERS, post-1956 military service needs a deposit before it counts toward eligibility or the annuity (OPM, retrieved 2026-10-13). The leave SCD adds civilian service and all honorable active-duty military service, because full credit is given for honorable active military service for leave accrual, deposit or not, unless you are a military retiree (OPM, retrieved 2026-10-13). The TSP SCD is the earliest civilian start you entered, and the vesting date is three years after it.

Leave without pay matters only past a threshold. Periods of nonpay over 6 months in a calendar year are not creditable and move the leave SCD later by that amount (OPM, retrieved 2026-10-13). The same 6-month line applies to retirement credit (OPM CSRS and FERS Handbook, chapter 20, retrieved 2026-10-13).

The four SCDs differ because each serves a different rule. The leave SCD sets your accrual rate. The retirement SCD tracks service creditable toward your eligibility to retire. The TSP SCD sets vesting in the agency automatic contributions. The reduction in force SCD sets seniority in a workforce restructuring and is not computed here (OPM, retrieved 2026-10-13).

4 hoursAnnual leave a pay period with less than 3 years of serviceOPM, retrieved 2026-10-13
6 hoursFrom 3 to under 15 years, 10 hours in the last pay period of the yearOPM, retrieved 2026-10-13
8 hoursAt 15 years and overOPM, retrieved 2026-10-13
30 daysAnnual leave carryover for most employees in the United States, 240 hours on a full-time scheduleOPM, retrieved 2026-10-13
3 yearsCivilian service to vest in the agency automatic 1 percent5 CFR 1603, retrieved 2026-10-13

A worked example

An employee served in the Army from June 1, 2000, to May 31, 2004, and has not paid the military deposit. Civilian service under FERS began March 14, 2006, and runs to October 13, 2026, with one long absence: leave without pay from January through August 2015, which is 2 months past the 6-month line. The rows are Military, no deposit (June 1, 2000, to May 31, 2004); Civilian service (March 14, 2006, to October 13, 2026); and Leave without pay over 6 months (July 1, 2015, to August 31, 2015).

The military period is 4 years, 0 months, 0 days. The civilian period is 20 years, 7 months, 0 days, and the 2 months of excess leave without pay bring it to 20 years, 5 months. The retirement SCD counts back only that civilian time from October 13, 2026: May 13, 2006. The leave SCD adds the 4 years of military service for 24 years, 5 months: May 13, 2002. With more than 15 years for leave, the accrual tier is 8 hours a pay period. The TSP SCD is March 14, 2006, and the agency 1 percent vested on March 14, 2009. Paying the military deposit would move the retirement SCD back to May 13, 2002, the same as the leave date.

What to do with your estimate

Compare the leave SCD with block 31 on your latest SF-50, using the guide to reading your SF-50, and see what the accrual tier means in federal leave rules. If the military deposit changes your retirement date, price it in the military buyback calculator, then carry your service into the retirement date finder and your pay history into the High-3 builder. Every other estimator is on the federal benefits calculators page.

FFEBA is an education organization. If you want someone to look at your own numbers, we can match you with a Federal Retirement Consultant (FRC), a professional trained on federal benefits. The FRC designation is listed with FINRA. The first review is free, nothing is booked until you choose a time, and you are never obligated to work with anyone we introduce. Get matched with an FRC.

Questions about this calculator

What is a service computation date?

A service computation date, or SCD, is a date built from your service history so that counting forward from it to today gives your creditable service. OPM recognizes four: leave, retirement, TSP and reduction in force. Each counts a slightly different set of service (OPM, retrieved 2026-10-13).

Why is my leave SCD different from my retirement SCD?

For most employees the two are the same (OPM, retrieved 2026-10-13). They split when service counts for one and not the other. Honorable active-duty military service counts toward the leave SCD for non-retired members, but under FERS post-1956 military service counts toward retirement only once the deposit is paid. Military retirees get leave credit only in limited cases.

Where do I find my SCD on the SF-50?

Block 31 of the SF-50 shows your leave SCD (OPM, retrieved 2026-10-13). The retirement SCD does not have its own block on the SF-50; ask your agency HR or benefits office for it. Your SF-50s are stored in your eOPF.

Does leave without pay change my service computation date?

Only the part over 6 months in a calendar year. OPM credits nonpay status up to 6 months in a calendar year; time beyond that is not creditable and pushes the leave and retirement SCDs later by the same amount (OPM, retrieved 2026-10-13).

When does the agency automatic 1 percent TSP contribution vest?

Under the TSP vesting rule, FERS employees keep the agency automatic 1 percent contributions and their earnings at separation only if they have completed three years of civilian service (5 CFR 1603, retrieved 2026-10-13). Some noncareer positions vest at two years. The calculator shows the date three years after your earliest civilian start.

Is this the SCD my agency uses?

No. This is an educational estimate on the dates you enter. Your agency computes the official SCDs from your verified records on the SF-144A or an equivalent worksheet. Use it to check a date that looks wrong or to see what a deposit or a period of leave without pay does.

Reviewed by the FFEBA education team. Last reviewed October 2026.

Sources

  1. U.S. Office of Personnel Management, Guide to Processing Personnel Actions, Quick Sheet: Determining Creditable Service for Leave (August 2026), retrieved 2026-10-13
  2. U.S. Office of Personnel Management, annual leave fact sheet, retrieved 2026-10-13
  3. U.S. Office of Personnel Management, CSRS and FERS Handbook, chapter 20 (creditable civilian service), retrieved 2026-10-13
  4. U.S. Office of Personnel Management, service computation date explainer (Federal Ball Park Estimator), retrieved 2026-10-13
  5. U.S. Office of Personnel Management, FERS service credit (military deposits), retrieved 2026-10-13
  6. Electronic Code of Federal Regulations, 5 CFR part 1603 (TSP vesting), retrieved 2026-10-13

Every government figure on this page carries its source and retrieval date. Worked examples are educational estimates on the assumptions shown, not a projection of any person's benefit. FFEBA is an education organization, not a financial advisor.

Keep reading

Read the rule behind the math.