Massachusetts Security Deposit Laws & Calculator

Massachusetts Security Deposit Law — Explained

The 1-Month Cap — Strictly Enforced

Massachusetts law (M.G.L. c. 186 § 15B) caps security deposits at exactly one month's rent. This is one of the few states where overcharging the deposit is itself a statutory violation that can trigger the triple-damage penalty — before you even move out. If you paid more than one month's rent as a security deposit at any point, you have a claim against your landlord independent of move-out deductions.

Mandatory Interest at 5% Per Year

Massachusetts landlords are required to hold security deposits in a separate, interest-bearing escrow account and pay the tenant 5% annual interest (or the actual bank rate if lower). This interest must be paid annually — either directly to the tenant or as a credit against rent — and any remaining interest balance must be returned along with the principal at the end of the tenancy.

This is not optional. Many Massachusetts landlords routinely fail to pay annual interest, creating an immediate violation of the statute. If you never received annual interest payments during your tenancy, the accumulated interest is part of your refund claim — and the failure to pay it is itself a violation that can trigger the triple-damage penalty.

The Move-In Statement Requirement

Within 10 days of move-in (or the collection of the security deposit, whichever is later), Massachusetts landlords must provide a written statement of the condition of the premises. Tenants have 15 days to add to this statement. This written record of condition is critical — at move-out, deductions can only be made for damage beyond what was documented at move-in. If your landlord never provided this statement, they have likely forfeited their right to make any deductions.

Bank Receipts and Annual Statements

Massachusetts landlords must provide the tenant with a receipt showing the name and address of the bank where the deposit is held within 30 days of receiving it. They must also provide annual statements showing the amount of interest earned. Failure to provide either document is an independent violation that can trigger the triple-damage penalty.

The Triple-Damage Penalty

Massachusetts imposes one of the highest statutory penalties for security deposit violations anywhere in the US. Under M.G.L. c. 186 § 15B(7), a landlord who violates any provision of the security deposit law — including failing to pay interest, not providing required receipts, missing the 30-day return deadline, or making improper deductions — is liable for three times the deposit amount plus interest, costs, and attorney fees. Courts have applied this penalty for purely procedural violations.

What to Do If Your Massachusetts Landlord Is Late

1. 1
   Review your move-in statement Did your landlord provide a written condition statement within 10 days of move-in? If not, document this fact — it may eliminate their deduction rights entirely.
2. 2
   Calculate all interest owed Add up 5% annual interest on your deposit for each year of the tenancy. If your landlord never paid annual interest, this accumulated amount is part of your claim.
3. 3
   Document your move-out thoroughly Take timestamped photos and video of every room before leaving. Compare against your move-in condition statement.
4. 4
   Provide your forwarding address in writing Email your new address to your landlord on move-out day. Massachusetts requires landlords to send the deposit and statement by the 30-day deadline.
5. 5
   Send a comprehensive demand letter Use RenterCalc's demand letter generator to cite M.G.L. c. 186 § 15B and demand the deposit, all accrued interest, and the triple-damage penalty for any violations.
6. 6
   File in small claims court or seek an attorney Massachusetts small claims limit is $7,000. For triple-damage claims exceeding this, a tenant rights attorney is recommended — many take these cases on contingency due to the large penalty exposure.

Security Deposit Laws in Nearby States

Compare Massachusetts's rules with neighboring New England states: