Rex says
It's usually small money, and it's still your money — and in a few cities the penalty for a landlord who skips it is multiples of the deposit itself.
Try a scenario
Click to load — tweak from there.Inputs
Set by state or city ordinance — often tied to a bank savings rate and republished each year.
Chicago, for example, historically applied a multiple of the deposit. Enter 0 to skip.
Result
Interest owed to you
$91.02
Deposit plus interest
$2,491.02
Average interest per year
$36.41
Statutory penalty if unpaid
$0
Total potential claim
$91.02
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How to use this
- 1Enter security deposit held ($).
- 2Enter annual interest rate required (%) — Set by state or city ordinance — often tied to a bank savings rate and republished each year..
- 3Enter months of tenancy.
- 4Enter compounding.
- 5Enter statutory penalty multiple if unpaid — Chicago, for example, historically applied a multiple of the deposit. Enter 0 to skip..
- 6Read your interest owed to you on the right — it updates as you type.
- 7Hit Share to keep the scenario or send it to someone.
About this calculator
If you rent in a jurisdiction with a deposit-interest rule — Chicago, New York City, New Jersey, Connecticut, Massachusetts, Minnesota, and others — your landlord holds your money in an interest-bearing account and owes you that interest at move-out or annually. This calculator compounds the rate across your tenancy and shows the total return, plus any statutory penalty for a landlord who never paid it.
Worked example
Using the values the calculator loads with:
Inputs
- Security deposit held: 2400 $
- Annual interest rate required: 1.5 %
- Months of tenancy: 30
- Compounding: Compounded annually
- Statutory penalty multiple if unpaid: 0
Results
- Interest owed to you: $91.02
- Deposit plus interest: $2,491.02
- Average interest per year: $36.41
- Statutory penalty if unpaid: $0.00
- Total potential claim: $91.02
What each field means
Inputs
- Security deposit held ($)
- The security deposit held used in the calculation, measured in $. Starts at 2400 $ so you have a working example on load.
- Annual interest rate required (%)
- Set by state or city ordinance — often tied to a bank savings rate and republished each year.
- Months of tenancy
- The months of tenancy used in the calculation. Starts at 30 so you have a working example on load. Accepted range: 0–480.
- Compounding
- Pick the option that matches your situation — the maths changes per option. Choices: Simple interest, Compounded annually.
- Statutory penalty multiple if unpaid
- Chicago, for example, historically applied a multiple of the deposit. Enter 0 to skip.
Results
- Interest owed to you
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Deposit plus interest
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Average interest per year
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Statutory penalty if unpaid
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Total potential claim
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
Which states require interest on security deposits?
Rules vary widely, but jurisdictions with deposit-interest requirements have included Connecticut, Massachusetts, Minnesota, New Jersey, New Mexico, New York, Pennsylvania (over a threshold and tenancy length), Rhode Island, and cities such as Chicago and San Francisco. Rates are usually republished annually, so check your city or state's current figure before filing a claim.
When does a landlord have to pay the interest?
Typically either annually during the tenancy or as a credit against rent, or in full when the deposit is returned after move-out. Deadlines for returning the deposit itself are commonly 14 to 45 days depending on the state.
What if my landlord never paid deposit interest?
Send a written demand citing the ordinance and the amount, keep a copy, and give a short deadline. If it's ignored, small claims court is the normal route — and in some cities the statute awards multiple damages plus attorney fees against a landlord who withheld it.
Is security deposit interest taxable?
Yes, interest paid to you is generally taxable interest income in the year you receive it, even though it's usually a small amount.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
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Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Security Deposit Interest Calculator — What Your Landlord Owes (2026). Retrieved from https://www.revenuelab.fyi/toolbox/security-deposit-interest-calculator
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/security-deposit-interest-calculator" target="_blank" rel="noopener">Security Deposit Interest Calculator — What Your Landlord Owes (2026) — RevenueLab</a> (2026).</p>
Source: [Security Deposit Interest Calculator — What Your Landlord Owes (2026) — RevenueLab](https://www.revenuelab.fyi/toolbox/security-deposit-interest-calculator) (2026).