Savings Deposit Program (SDP): 10% Guaranteed Interest During Deployment

The examples below use 2026 rates and are for illustration only. Actual outcomes depend on deployment length, deposit timing, and individual circumstances.

What is the Savings Deposit Program?

The Savings Deposit Program is a government-backed savings account available to service members deployed to designated combat zones. It pays 10% annual interest on deposits up to $10,000.

That number stops people. Ten percent. Guaranteed. Backed by the U.S. Treasury.

Commercial savings rates change with the interest rate environment. SDP's 10% rate is fixed by program rules while eligible deposits qualify. It carries no market risk and no rate-cycle uncertainty — the 10% is what it is regardless of what savings rates do.

It's administered through your finance office, not a bank. You won't find it on a website with a slick app. Most service members deploy without ever knowing it exists.

Who is eligible for SDP?

Eligibility requires two things:

1. Combat zone designation — you must be deployed to a Presidential Executive Order-designated combat zone or contingency operation. Your finance office can confirm whether your specific location qualifies.

2. 30-day threshold — you must serve at least 30 consecutive days in the qualifying area, OR at least one day in each of three consecutive months.

If you're receiving Hostile Fire Pay or Imminent Danger Pay, that's a reliable signal that you likely qualify — but verify with finance.

SDP is available to all ranks, all branches — active duty, Guard, and Reserve members who are mobilized and meet the threshold.

How does the SDP interest math work?

SDP pays 10% annual interest. Military OneSource describes the interest as compounding monthly. Interest continues to accrue for up to 90 days after departure from the combat zone. Here's what that looks like at the $10,000 maximum deposit:

It is difficult to find another government-backed savings opportunity with a fixed 10% annual rate and principal protection.

The 90-day grace period matters: even after you leave the combat zone, interest keeps accruing for up to 90 more days. A 6-month deployment where $10,000 is deposited and held through the 90-day grace period earns interest on roughly 9 months total — approximately $750.

How do you enroll in SDP?

1. Contact your finance office — at your installation before deployment or at your deployed location once you arrive. There's no online enrollment portal.

2. Complete DD Form 2558 — Authorization to Start, Stop, or Change an Allotment. This is how the money moves from your pay into the SDP account.

3. Set your deposit amount — you can deposit up to $10,000 total. Military OneSource states that deposits can generally begin after 31 days in the combat zone. Deposits cannot exceed your monthly pay and allowances after allotments unless more than one month of unallotted pay is approved in writing by your commander.

4. Keep your deposit confirmation — get a receipt or written confirmation from finance. You'll need documentation when you request withdrawal after returning.

Once eligible, depositing earlier generally increases total interest earned, but make sure you maintain enough cash flow for bills, family expenses, and emergencies.

When do you get your money back?

Interest accrues for up to 90 days after you leave the combat zone. After that 90-day window closes, the account stops earning interest — but the funds remain available.

Withdrawal is typically processed through DFAS. Contact your finance office after returning to initiate the withdrawal. You'll receive your principal plus all accrued interest.

If you don't request withdrawal promptly after the 90-day window, the money doesn't disappear — it just stops growing. After the interest period ends, consider moving the funds to another savings or investment option that fits your financial plan.

What SDP does NOT do

A few important limits to understand:

It's not a retirement account. The growth is great, but there's no tax-advantaged treatment after withdrawal. The $750 you earn on a 9-month deployment goes into your pocket as taxable income.

The $10,000 cap is a hard limit. SDP is a short-term savings tool, not a wealth-building vehicle. It's most valuable when treated as one piece of a larger deployment savings plan.

It doesn't replace TSP. The long-term compounding advantage of Roth TSP contributions during a combat zone deployment — money that's never taxed at any stage — significantly exceeds the SDP return over a 20–30 year horizon. SDP and TSP serve different purposes.

Interest is taxable. SDP interest is generally taxable income, even if earned during a combat zone deployment. While combat zone pay itself may be excluded from federal income tax under CZTE, the interest earned on SDP deposits is generally taxable. State treatment may vary. Verify with your finance office or a tax professional.

Is SDP interest income taxable?

This is the most commonly asked question about SDP.

SDP interest is generally taxable income, even if earned during a combat zone deployment. While combat zone pay itself may be excluded from federal income tax under CZTE, the interest earned on SDP deposits is generally taxable. State treatment may vary. Verify with your finance office or a tax professional before assuming any tax exclusion applies to the interest.

Even accounting for federal income tax on the interest, the after-tax return on SDP generally compares favorably to most low-risk savings options available. The exact impact depends on your marginal tax rate and applicable state rules.

The deployment money stack: SDP + Roth TSP

Most service members who max SDP also use the deployment period to accelerate Roth TSP contributions. These two strategies are complementary:

The SDP handles a fixed, risk-free $10,000. TSP handles the rest of your available cash flow. Together, a disciplined E-5 or E-6 on a 9-month deployment can realistically bank $30,000–$50,000 in new savings — most of it with significant tax advantages.

Note: in a combat zone, the total annual additions limit for TSP rises to $72,000 — but Roth TSP contributions are capped at $24,500 (the elective deferral limit). Contributions above $24,500 from tax-exempt combat-zone pay go into the traditional tax-exempt portion of TSP, not Roth.

Before you deploy: steps to consider

For service members heading to a qualifying combat zone:

1. Check SDP eligibility early — ask your finance office whether your specific area qualifies before or immediately after arrival. Eligibility is confirmed at the unit level.

2. Enroll through finance after the 31-day threshold — once eligible, depositing earlier generally increases total interest earned. Maintain enough liquidity for family expenses and emergencies before committing funds.

3. Review your available cash flow — deployment typically reduces variable expenses significantly. Understanding what's available beyond the $10,000 SDP cap helps clarify what can go toward other savings vehicles.

4. Consider adjusting your TSP contribution rate in MyPay — for service members looking to increase Roth TSP contributions during deployment, updating the election before departure means contributions begin immediately when CZTE-eligible pay starts. Adjustments can be made at any time.

5. Review SGLI and beneficiary designations — not a financial growth question, but a critical step before any deployment.

For more tools and guides for mid-career financial decisions — PCS, deployment, and duty station comparison — see Navigating Service.

Last reviewed: May 2026. SDP rules and rates are set by DoD regulation. Verify current eligibility criteria and enrollment procedures with your finance office. This is financial education, not advice.