Calculate returns from the Savings Deposit Program, which pays 10% annual interest on deposits up to $10,000 for service members deployed to designated combat zones.
Rates last verified September 2026 against the published source tables.
SDP pays 10% annual interest, compounded quarterly, on deposits up to $10,000 — a guaranteed rate no civilian savings product matches. Eligibility starts after 30 consecutive days in a designated combat zone, or one day in each of three consecutive months, and deposits are made through your finance office rather than online. The interest is taxable even though the deployment pay funding it usually is not.
Interest keeps accruing for 90 days after you leave the zone, then stops, so leaving the money in past that earns nothing. Withdrawals before the deployment ends are permitted only in specific hardship cases; otherwise the balance and interest are paid out automatically after the 90-day tail. Filling the $10,000 cap early in a deployment is what maximizes the return, since the ceiling is on principal rather than on contributions.
Before you qualify. Eligibility starts after 30 consecutive days in a designated combat zone, or one day in each of three consecutive months. A shorter deployment, or a deployment somewhere that is not designated, pays nothing at all — the program is not open to every deployment.
On anything above the cap. Interest is paid on principal up to $10,000. Accrued interest can carry the balance above that, and the excess earns nothing — so once you are at the cap the return is flat rather than compounding.
More than 90 days after you leave. Interest continues for 90 days after you leave the zone and then stops. Money left in past that point is money not earning, which is the one avoidable loss in the program.
Deposits go through finance in theater. You cannot open an SDP account online. It is done through the finance office at the deployed location, by cash, check or allotment — which is why filling the cap early takes planning before you leave rather than after you arrive.
The payout is automatic, the timing is not instant. The balance and interest are returned after the 90-day tail, usually by direct deposit to the account on your LES. Ask finance to confirm the account before you redeploy: a stale account is the usual reason a payout goes missing, and 10% a year stops accruing whether or not the money has reached you.
The interest is taxable. SDP interest is taxable income even though the pay that funded it usually was not, and it is reported to you for the year it is paid. Set something aside for it rather than being surprised at filing time.
SDP is a Department of Defense savings account available to service members deployed to designated combat zones or qualifying hazardous duty areas. It pays a guaranteed 10% annual return, credited quarterly at 2.5% on the average quarterly balance — far above any commercial savings account — and is backed by the US government, so the return is not market-dependent. Interest is credited on the balance up to the $10,000 cap; once you reach the cap the return is effectively a flat $1,000 per year.
You become eligible once you are receiving hostile fire or imminent danger pay and have served more than 30 consecutive days in a designated combat zone or qualifying area, or one day in each of three consecutive months. Enrollment is handled through your finance or disbursing office in theater, not before you deploy. Because interest only accrues on money actually deposited, enrolling and depositing as early in the deployment as possible is what drives the return.
Deposits are capped at $10,000 in total, and you cannot deposit more than your unallotted current pay and allowances in any given month. This means reaching the cap takes several months for most members — which is why total interest depends heavily on how early in the deployment you start contributing, not just on deployment length.
Interest continues to accrue for 90 days after you leave the combat zone, then stops. Funds are normally returned automatically after that window, though you may request an earlier withdrawal. Because of that 90-day tail, leaving the money in place until interest stops is almost always worth it.
Yes. The interest SDP pays is taxable income and is reported to the IRS, even though the underlying deposits may have come from tax-exempt combat-zone pay. The deposits themselves are simply your own money returned and are not taxed again. Budget for the tax on the interest portion when you file. Tax-exempt combat-zone pay is often better directed at Roth TSP contributions, where qualified growth comes out untaxed.