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Calculator · Deployment Pay

Savings Deposit Program (SDP) Calculator

SDP pays a guaranteed 10% annual return on up to $10,000 while you're deployed to a combat zone — about $1,000 over a 12-month deployment if you max it early. It's the best risk-free return the government will ever hand you. Interest compounds quarterly and keeps accruing for 90 days after you leave the zone.

Max deposit (earns interest)$10,000
Interest rate10% / yr · 2.5% per quarter
CompoundingQuarterly
Interest accrues until90 days after you leave the combat zone
Eligibility≥ 30 consecutive days deployed (or 1 day in 3 consecutive months)
Taxable?Interest is taxable income; deposits are not

Run your deployment

Estimated payout

Interest earned (estimate)
$1,000
You deposited
$10,000 lump on day one
$10,000
Interest @ 10%/yr (2.5%/quarter)
9 mo deployed + 90-day grace · compounded quarterly
$1,000
Ending balance
Principal + accrued interest at payout
$11,000
Front-load it. Maxing the full $10,000 the day you're eligible instead of trickling it in over 9 months earns about $248 more interest on the same money. Every quarter your cash sits in there is 2.5% you can't get back.
Reality check: This is a PLANNING ESTIMATE. It applies 10%/yr compounded quarterly to a $10,000 interest-earning base and adds the 90-day post-deployment grace. By a stated assumption, it caps the interest-earning base at $10,000 and does not model interest accrued above that ceiling — so your real return may run slightly higher than shown. Exact accrual depends on your deposit dates and DFAS posting. Confirm your actual balance in myPay and with DFAS before counting on a number.
What nobody briefs you on
  1. 10% guaranteed is unheard of. No savings account, no CD, no money-market fund on earth pays a risk-free 10%. SDP is the single best return the government ever hands you. If you're deployed and not using it, you're leaving free money on the FOB.
  2. Get to $10,000 fast. Only the first $10,000 earns interest. The sooner you hit the cap, the more quarters that full balance compounds. Front-loading beats trickling — the math above shows exactly how much.
  3. The clock stops 90 days after you leave. Interest keeps accruing for 90 days past your departure from the combat zone, then it's done. Don't pull your money the day you redeploy — let that last quarter ride.
  4. The interest is taxable. Your deposits are already-earned pay, so those aren't taxed again — but the interest SDP pays you is taxable income. It shows up at tax time. Budget for it; don't get surprised.
  5. You have to set it up. SDP isn't automatic. You enroll in-theater through your finance office (DFAS), usually after 30 days in the zone. Ask early — nobody's going to chase you down to enroll you.
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Frequently Asked Questions

How much interest does SDP pay?

The Savings Deposit Program pays a guaranteed 10% per year, compounded quarterly (2.5% each completed quarter), on balances up to $10,000. That is a risk-free 10% return — no civilian savings account, CD, or money-market fund comes close. On a maxed $10,000 balance, you earn roughly $1,000 over a 12-month deployment.

How much can I put in the Savings Deposit Program?

You can deposit up to $10,000 of unallotted pay into SDP. Only that first $10,000 earns the 10% interest, so the sooner you reach the cap, the more quarters your full balance compounds. Front-loading the $10,000 early in a deployment earns more than spreading the same money out over several months.

When does SDP interest stop?

Interest keeps accruing for 90 days after you leave the combat zone, then it stops. Because of that grace period, you should not pull your money out the day you redeploy — leaving it in lets that final quarter of interest accrue before the program closes out your balance.

Is SDP interest taxable?

Yes. The interest SDP pays you is taxable income and shows up at tax time. Your deposits themselves are already-earned pay, so the principal you put in is not taxed again — only the interest is. Budget for the tax on the interest so it is not a surprise.

Who is eligible for SDP?

You are eligible if you are deployed to a designated combat zone or qualifying contingency operation for at least 30 consecutive days, or for at least one day in each of three consecutive months. Enrollment is not automatic — you sign up in-theater through your finance office (DFAS), usually after 30 days in the zone.

Official Sources

Published by the Honest MOS Editorial DeskVerified against DoD/.gov sourcesUpdated May 2026Editorial standards