Free calculator · Maryland law
Maryland security deposit interest calculator
Maryland landlords owe simple interest on security deposits of $50+ held at least 6 months, and must return deposit plus interest within 45 days of tenancy end (Md. Real Property § 8-203). Calculate the statutory minimum below.
Interest owed under § 8-203
$0.00
Enter the deposit amount and both dates to see the amount owed.
Each year’s rate is the greaterof 1.5% or the 1-year U.S. Treasury rate on that January’s first business day. For 2026 that is 3.47%. The full year-by-year table is below the calculator.
Cross-check: Maryland DHCD official calculator ↗Landlords must return the deposit with interest within 45 days after the tenancy ends (Md. Real Property § 8-203). Estimates only, not legal advice.
Official rates
Maryland security deposit interest rates by year
The statute sets each year’s rate at the greater of 1.5% or the 1-year U.S. Treasury yield on the first business day of January. The 2026 rate is 3.47%. The calculator applies these year by year to the months your deposit was held.
| Year | 1-yr Treasury (Jan) | Rate applied |
|---|---|---|
| 2026 | 3.47% | 3.47% |
| 2025 | 4.17% | 4.17% |
| 2024 | 4.80% | 4.80% |
| 2023 | 4.72% | 4.72% |
| 2022 | 0.40% | 1.50%(floor) |
| 2021 | 0.10% | 1.50%(floor) |
| 2020 | 1.56% | 1.56% |
| 2019 | 2.60% | 2.60% |
| 2018 | 1.83% | 1.83% |
| 2017 | 0.89% | 1.50%(floor) |
| 2016 | 0.61% | 1.50%(floor) |
| 2015 | 0.25% | 1.50%(floor) |
By hand
How do I calculate Maryland security deposit interest by hand?
Count the full months the deposit was held, credit each month at one twelfth of that calendar year’s rate, and add the months up. No compounding, no credit for a partial month. Four steps:
- Write down the deposit amount and the day the tenant paid it. Interest starts that day, not on the lease start date.
- Count full months from that day to the day the tenancy ended. Thirty days that fall short of a full month earn nothing.
- For each month, multiply the deposit by that year’s rate from the table above and divide by 12.
- Add the months together. That total, plus the deposit, is what goes back to the tenant within 45 days.
Worked example: a $2,400 deposit paid September 1, 2023 on a Columbia townhouse, tenancy ending September 1, 2026. That is 36 full months. Four months of 2023 at 4.72% earn $37.76. Twelve months of 2024 at 4.80% earn $115.20. Twelve months of 2025 at 4.17% earn $100.08. Eight months of 2026 at 3.47% earn $55.52. Total interest owed: $308.56, so the refund check reads $2,708.56 before any itemized deductions. The calculator above does the same walk in one click.
Inputs
What does a Maryland security deposit calculator need from me?
Three things: the deposit amount, the date the tenant paid it, and the date the tenancy ended. Everything else (the yearly rate, the 1.5% floor, the $50 minimum, the six month holding threshold) is baked into the tool from the statute. If the tenant paid the deposit in two installments, run each installment separately and add the results. If a pet deposit was collected under the same lease, it counts toward the one month cap and earns interest the same way.
One thing the calculator will not tell you is what a landlord may deduct. Unpaid rent, damage beyond ordinary wear and tear, and losses from a lease breach are the only three categories, and each one needs a written itemized statement mailed within the same 45 days. The 45 day return rule guide covers the deduction side in detail.
Statewide
Does the calculator work for Howard County, Baltimore, and Montgomery County rentals?
Yes. Security deposit interest is set by state law in Real Property § 8-203, so the same rate table applies to a Columbia single family home, a Baltimore City rowhouse, a Silver Spring condo, and a Frederick townhouse. Counties and cities layer their own rental licensing and inspection rules on top, and Montgomery County and Baltimore City run their own landlord tenant offices, but none of them change the interest formula. What changes by jurisdiction is the license you need to hold the deposit legally in the first place; our county pages, starting with Howard County, cover that.
Tenants use this page as much as landlords do. If a refund arrived without interest, or with interest computed at a flat 1.5% for years when the Treasury rate was higher, the number above is what you can point to. Landlords who run the calculation before writing the check rarely hear from a tenant again.
FAQ
Maryland deposit rules, answered
Do Maryland landlords owe interest on security deposits?＋
Yes, when the deposit is $50 or more and has been held at least 6 months. Under Md. Real Property § 8-203, interest is simple (not compounded), accrues in full monthly intervals from the day the tenant pays the deposit, and must be returned with the deposit within 45 days after the tenancy ends.
What interest rate applies to Maryland security deposits?＋
For each year, the greater of 1.5% per year or the daily U.S. Treasury yield curve rate for 1 year as of the first business day of that year. For 2026 the rate is 3.47%. In low-rate years like 2021 and 2022 the 1.5% floor applied; in 2023 and 2024 the Treasury rate pushed it to 4.72% and 4.80%. The calculator above applies each calendar year's rate to the months the deposit was held in that year.
What is the Maryland security deposit interest rate for 2026?＋
3.47%, the 1-year U.S. Treasury yield on January 2, 2026, which beats the 1.5% statutory floor. It applies to months a deposit is held during 2026 regardless of when the tenancy started.
How much can a Maryland landlord collect as a security deposit?＋
Since October 1, 2024 (HB 693, the Renters' Rights and Stabilization Act), the maximum is one month's rent, down from the previous two-month cap. Charging more exposes the landlord to penalties of up to three times the excess.
What happens if the deposit isn't returned within 45 days?＋
A landlord who withholds a deposit without a valid reason (unpaid rent, damage beyond wear and tear, or losses from a breach) can be liable for up to three times the withheld amount plus reasonable attorney's fees.
Deposits, interest, and the 45-day clock are exactly the kind of compliance we handle for owners. See what full management covers or get a free rental analysis.