CRSC and buying back military time

Information verified through September 10, 2026.

The short answer. To credit your military service toward a federal civilian retirement under FERS or CSRS, you generally have to waive your military retired pay. Combat-Related Special Compensation is built on being entitled to that retired pay. So the waiver that unlocks the civil-service credit is the same waiver that closes the door on CRSC, and the Department of Defense CRSC program guidance says so in two separate places. There is one important exception, and it is in the Office of Personnel Management's own rule: retirees whose retired pay was awarded for a disability incurred in combat with an enemy of the United States, or caused by an instrumentality of war during a period of war, and reserve retirees under Chapter 1223, may be able to credit the service without waiving anything.

What "buying back your military time" actually means

The phrase is shorthand for two things that get bundled together at a new-employee briefing and then come apart later, at the worst possible moment.

The first is the military service deposit. OPM's rule is clean: military service performed before 1957 is creditable without a deposit, and military service performed on or after January 1, 1957 requires a deposit to be paid in order to credit the service, both to establish title to an annuity and to compute it. The deposit is a percentage of the military basic pay you earned, plus interest, and it is generally 3 percent under FERS and 7 percent under CSRS. There is an interest-free window early in your federal employment, after which interest compounds annually. FERS employees apply on Standard Form 3108; CSRS employees use Standard Form 2803. Get your real number from your payroll office. Do not budget off a percentage you read on a website, including this one.

The second is the waiver of military retired pay. This is the part that matters to a CRSC recipient, and it is the part that tends to get one sentence in the briefing.

The rule that catches retirees

OPM states it plainly on its FERS page: you cannot receive credit for any military service in your FERS retirement computation if you are receiving military retired pay, unless you were awarded that retired pay due to a service-connected disability either incurred in combat with an enemy of the United States or caused by an instrumentality of war and incurred in the line of duty during a period of war, or under the provisions of Chapter 1223, Title 10, United States Code. The CSRS page carries the same rule in nearly identical language.

If neither exception applies to you, OPM's remedy is the waiver: you can elect to waive the retired pay and have the military service added to your civilian service in computing the annuity. OPM even supplies the wording and the address. The waiver goes to the Defense Finance and Accounting Service, U.S. Military Retirement Pay, 8899 E 56th Street, Indianapolis, IN 46249-1200, and OPM advises sending it at least 60 days before your planned retirement. Some agency guides say 90. Give yourself the longer runway.

Now put that next to what CRSC requires.

The DoD guidance says it twice

The Combat-Related Special Compensation program guidance lists four Preliminary CRSC Criteria that a retiree has to satisfy before anyone even looks at whether a condition is combat-related. The third one is entitlement to retired pay, "notwithstanding that such retired pay may be reduced due to receipt of VA disability compensation." Then it adds a subparagraph that leaves no room:

That alone would settle it. The guidance then says it a second time, from a different direction, in the section that computes the monthly amount. The maximum CRSC payment cannot exceed the current reduction in retired pay caused by the VA offset, and so, the guidance explains, CRSC is not payable if there is no such reduction, including "because the member is not receiving retired pay for other reasons (such as a member who waives military retired pay in order to credit military service for a civil service retirement)."

Two independent mechanisms, same result. The first disqualifies you at the front gate. The second, even if you somehow got through the gate, computes your entitlement to zero, because CRSC is a restoration of retired pay that the VA offset took away, and you cannot restore pay you gave up. This is the same structural logic behind why CRSC and CRDP cannot be paid together and why the CRSC versus CRDP comparison turns on your retired pay ceiling rather than on your VA rating.

The exception a lot of retirees never hear about

Read OPM's exception again with a CRSC packet in front of you:

The first bullet uses two of the same phrases that decide CRSC cases. "Instrumentality of war" is one of the four combat-related categories, and we have written a whole guide on what actually counts as an instrumentality of war. That overlap is not a coincidence; both bodies of law borrow from the same older concept of a war-incurred disability.

It is also not a shortcut. Three cautions, and we would rather you hear them from us than find out later:

• The test is about your retirement, not your VA rating. OPM keys on what the retired pay was awarded for. That points at a Chapter 61 disability retirement and the findings behind it, not at what the VA service-connected afterward. A retiree who left on a 20-year longevity retirement and later got a combat-related VA rating is generally not in this exception. If you are a Chapter 61 medical retiree, this paragraph deserves a hard look.
• "During a period of war" is a defined term, and it attaches to the instrumentality-of-war half of the sentence. Whether a given date falls inside a statutory period of war is a legal determination, not a judgment call, and it is not ours to make for you.
• The exception covers the waiver, not the deposit. You still owe the post-1956 deposit to get the service credited. What you may avoid is giving up the pay.

If you fit, the outcome is the good one: military service counted in your civilian annuity, military retired pay still flowing, CRSC eligibility untouched. That is worth a written determination from your agency benefits office. Ask for it in writing, cite OPM's Military Retired Pay page for FERS or CSRS by name, and keep the answer with your retirement file.

How to price the trade honestly

If the exception does not apply, this becomes an arithmetic problem, and it is worth doing carefully because it is close for some people and lopsided for others.

What you would be giving up: your military retired pay, plus CRSC. CRSC is exempt from federal income tax, which the DoD guidance records as a determination of the Armed Forces Tax Council under section 104 of title 26. That tax treatment is a bigger part of CRSC's value than most comparisons account for.

What you would be gaining: additional years of creditable service in a FERS or CSRS annuity, which is generally taxable, plus whatever the added service does for retirement eligibility dates. For some people the buyback also changes when they can retire, which is a real benefit that does not show up in a monthly-dollar comparison.

So the comparison that actually answers the question is: after-tax military retired pay plus tax-free CRSC, for life, against the after-tax increase in your civilian annuity attributable to the bought-back years, for life, minus the cost of the deposit. Not this month against next month.

One more variable that people forget: CRSC amounts are not static. They move with your VA rating, with dependents, and with the annual cost-of-living adjustment. A comparison built on today's figure understates the CRSC side over a thirty-year horizon.

What this means for military retirees

Most veterans who take a federal job are not military retirees. They served, separated, and the buyback is close to a pure win for them. That is why the briefing is enthusiastic, and the briefing is not wrong for that audience.

Military retirees are a different case, and CRSC recipients are a different case again. If you are already receiving CRSC, or you have a live application, or you are a Chapter 61 retiree who has not applied yet, the buyback decision and the CRSC decision are the same decision. They cannot be sequenced independently. We see the same pattern with retirees who work while drawing CRSC: the employment itself is fine, and it is the paperwork attached to it that creates the problem.

There is one thing we will not tell you, because we cannot verify it: whether a waiver already signed can be undone. That claim circulates, and we have not found a primary source that establishes a general right to revoke. Treat the waiver as permanent when you are deciding, and if you have already signed one, ask DFAS directly what your options are rather than assuming either the best case or the worst.

What you should do now

1. Find out which kind of retirement you have. Pull your retirement orders and your DD Form 214. Chapter 61 disability retirement, 20-year longevity retirement, and Chapter 1223 reserve retirement lead to three different answers here.
2. Ask your agency benefits office, in writing: "Based on my retirement, does the OPM exception for retired pay awarded for a disability incurred in combat with an enemy of the United States, or caused by an instrumentality of war and incurred in line of duty during a period of war, apply to me? If not, does the Chapter 1223 exception apply?" Keep the reply.
3. Get the deposit estimate in dollars from your payroll office, along with the interest-free deadline. Ask for the figure with and without further interest.
4. Call DFAS Retired and Annuitant Pay at 800-321-1080 and ask what a waiver would do to your retired pay account and to any CRSC on it. Note the date, the representative, and the answer.
5. Know your CRSC number before you compare anything. If you are already approved, your award letter and your Retiree Account Statement have it. If you are not, treat it as an estimate.
6. Check your effective dates. CRSC runs per condition, and if you have not read our guide on how CRSC effective dates work, the retroactive side of your file may be worth more than you think, which changes the math.
7. Do not sign anything on the day of the briefing. Nothing in this process expires that week.

If you retired from the Army, your CRSC determinations run through Army HRC, and the other branches each have their own office. Whichever branch you came from, the office that made your CRSC award is the one that can tell you how a status change would be recorded.

Frequently asked questions

The bottom line

Buying back military time is a good deal for most veterans and a genuine decision for military retirees. For a retiree drawing CRSC it is neither a formality nor a trap, it is a trade with a written price: the DoD guidance disqualifies a member who waives retired pay to credit service toward a civil service retirement, and it says so twice so that nobody has to guess.

The part worth chasing down is the exception. If your retired pay was awarded for a disability incurred in combat with an enemy of the United States, or caused by an instrumentality of war during a period of war, or you retired under Chapter 1223, you may be able to have the credit and keep the pay. That is a written determination somebody in your agency can make, and it is worth the email.

If you want a second set of eyes on where your CRSC stands before you make the call, that is a short conversation and we are glad to have it. Flat fee if you decide to work with us, never a percentage, and nothing about the first call costs anything. You can also have an existing packet reviewed if you already filed.

Sources: Department of Defense, Combat-Related Special Compensation, Revised Program Guidance (January 2004), Attachment 1, published at militarypay.defense.gov — Preliminary CRSC Criteria paragraph 3 (entitlement to retired pay notwithstanding VA offset) and paragraph 3.a (waiver for civil service retirement disqualifies), Monthly Amount of CRSC paragraph c (Maximum Amount, CRSC not payable where the member is not receiving retired pay, including a waiver to credit service for a civil service retirement), the Armed Forces Tax Council determination that CRSC payments are exempt from federal income tax under 26 U.S.C. § 104, and the CRSC and CRDP election rule; U.S. Office of Personnel Management, Military Retired Pay (FERS Information) — the bar on crediting military service while receiving military retired pay, the two exceptions, the waiver election, the DFAS mailing address and the 60-day lead time; OPM, Military Retired Pay (CSRS Information) — the parallel CSRS rule; OPM, Creditable Service (FERS Information) — military service before 1957 creditable without deposit, service on or after January 1, 1957 requiring a deposit to establish title to or compute an annuity, and Standard Form 3108; 10 U.S.C. § 1413a (Combat-Related Special Compensation); 5 U.S.C. §§ 8332 and 8411 (creditable service, CSRS and FERS); Congressional Research Service, Credit for Military Service Under Civilian Federal Employee Retirement Systems, Report R40428. Deposit percentages (3 percent FERS, 7 percent CSRS of military basic pay, plus interest) are the general rates and should be confirmed against your own payroll office estimate.

This article is provided for general educational purposes and is not legal advice, financial advice, or a guarantee of CRSC eligibility, approval, effective date, or payment amount. Rules, guidance, and implementation procedures can change. Veterans should verify current requirements with their military department, DFAS, the Department of Veterans Affairs, or an appropriately accredited representative.