What are the security deposit rules in Massachusetts?

Verified July 8, 2026 All Massachusetts topics →

Pending legislation — not yet law. The rules on this page reflect current law only. The following bill would change it if enacted:

HD2501 / 'An Act enabling local options for tenant protections' (194th General Court, 2025-2026) — Would repeal G.L. c. 40P (the Massachusetts Rent Control Prohibition Act) and replace it with a local-option regime letting municipalities cap annual rent increases at the lesser of CPI or 5% and adopt just-cause eviction. Perennial refile of prior sessions' H.1304/H.1378/H.2103, none of which advanced.Status: Filed in the 194th General Court; in committee; not enacted as of the checked date. Chapter 40P remains fully in force. (checked 2026-07-08).

Massachusetts caps security deposits at one month's rent — and at move-in a landlord may collect only first month, last month, that deposit, and the cost of a new lock and key, nothing else.

The deposit must go into a separate interest-bearing Massachusetts bank account with a bank receipt to the tenant within 30 days, a signed statement of condition must be delivered within 10 days of move-in, 5% (or actual bank-rate) interest is owed annually, and within 30 days of move-out the landlord must return the deposit or deliver an itemized damage list sworn under the pains and penalties of perjury with written cost evidence. The statute is strict liability: miss the bank account, the 30-day list, or the 30-day return and the landlord forfeits the entire deposit — and the account, transfer, and return failures trigger mandatory treble damages plus interest, costs, and attorney's fees. Every one of these rights is non-waivable, which is why Massachusetts attorneys routinely advise small landlords that the safest security deposit in Massachusetts is the one you never collect.

Massachusetts security deposits at a glance

Maximum deposit	1 month's rent — G.L. c. 186, § 15B(1)(b): at or before move-in, total charges may not exceed first month's rent + last month's rent (at the same rate as the first) + a security deposit equal to first month's rent + the purchase and installation cost of a key and lock. Nothing else may be demanded, and as amended effective 2025-08-01 the restriction expressly binds the lessor's agents too. After commencement, the landlord may never demand advance rent beyond the current month or a deposit above the allowed amount (§ 15B(1)(d)) — meaning the deposit stays pegged to the ORIGINAL first month's rent even after increases. Vacation/recreational rentals of 100 days or less are exempt from the entire section (§ 15B(9)).
Return deadline	30 days
Deadline conditions	Within 30 days after termination of occupancy under a tenancy at will or the end of the tenancy specified in a valid written lease (§ 15B(4)). The clock runs from termination; there is no forwarding-address precondition for the deposit itself (though the last-month's-rent interest receipt tells tenants to leave a forwarding address for interest delivery).
Itemization required	Yes
Itemization rules	Deductions are limited to exactly three categories (§ 15B(4)): (i) unpaid rent or water charges not validly withheld, (ii) unpaid real-estate-tax increases owed under a § 15C-compliant tax escalation clause, and (iii) reasonable repair costs for tenant-caused damage beyond reasonable wear and tear. For damage deductions the landlord must deliver, within the same 30 days, an itemized list SWORN UNDER PAINS AND PENALTIES OF PERJURY describing the damage and repairs in precise detail, with written evidence of cost (estimates, bills, invoices, or receipts). No deduction is allowed for damage listed on the move-in statement of condition (or the tenant's accepted addendum) unless the landlord repaired it and proves the new damage is unrelated. No deduction may be made for any other purpose.
Separate account required	Yes
Interest owed to tenant	Yes
Account & interest rules	The deposit must be held in a separate interest-bearing account in a Massachusetts bank, beyond the reach of the landlord's creditors including foreclosing mortgagees and bankruptcy trustees, with transfer provisions for subsequent owners (§ 15B(3)(a)). A bank receipt (bank name and location, amount, account number) must be given within 30 days of receipt — failure entitles the tenant to immediate return. If held one year or longer, interest accrues from day one at 5% per year or the actual bank rate if lower, payable at each tenancy anniversary with an annual statement; if the landlord fails to pay or send the deduct-from-rent notice within 30 days of year end, the tenant may self-help by deducting the interest from rent (§ 15B(3)(b)). Last month's rent collected in advance separately earns the same 5%-or-bank-rate interest with its own receipt requirements, and failure to pay THAT interest within 30 days of termination carries an automatic treble-interest penalty plus costs and fees (§ 15B(2)(a)).
Pet deposits	Not permitted as a separate charge: § 15B(1)(b)'s exclusive list of move-in charges leaves no room for pet deposits or pet fees on top of first, last, one-month deposit, and lock/key cost.
Non-refundable fees allowed	No
Penalty for violation	Two tiers. Forfeiture (§ 15B(6)): the landlord loses the right to retain ANY portion of the deposit — and to counterclaim for damage in a tenant's recovery suit — for (a) failing to hold funds in a compliant account, (b) failing to furnish the itemized damage list within 30 days, (c) putting a conflicting provision in a signed lease and attempting to enforce it or seeking a waiver, (d) failing to transfer the deposit on sale, or (e) failing to return the deposit or balance with interest within 30 days. Treble damages (§ 15B(7)): violations of (6)(a), (d), or (e) mandate three times the deposit or balance due plus 5% interest, court costs, and reasonable attorney's fees. The Attorney General's consumer-protection regulations (940 CMR 3.17) additionally make § 15B violations unfair practices under c. 93A, which carries its own multiple-damages exposure.
Tenant forwarding-address duty	Not addressed by statute

Notes and caveats

This is the most trap-laden deposit statute in the dataset; page copy should be structured as a compliance checklist. Key traps verified in the full text: (1) the sworn-under-perjury itemization with documentary evidence is required for ANY damage deduction; (2) the deposit cannot be topped up after a rent increase (§ 15B(1)(d) pegs it to the original first month's rent — masslandlords.net teaches the same conservative reading); (3) the record-keeping duty (§ 15B(2)(d)) gives tenants inspection rights, and wrongful refusal alone triggers immediate-return liability; (4) last month's rent is a parallel regulated instrument with its own receipt, interest, and treble-interest penalty; (5) forfeiture under (6)(b) (late itemized list) does NOT carry § 15B(7) treble damages — only (6)(a), (d), and (e) do — a distinction courts enforce and secondary sources routinely get wrong. New since batch planning: St. 2025, c. 9 (eff. 2025-08-01) extended § 15B(1)(b) to agents and authorized EOHLC-regulated optional 'fee in lieu of deposit' arrangements (non-refundable, total capped at one month's rent, tenant opt-out preserved) — regulations status should be re-checked at the next verification sweep. The related 2025 broker-fee law (c. 112, § 87DDD1/2) makes the hiring party — usually the landlord — pay broker fees effective 2025-08-01, closing the old move-in-cost loophole. Vacation rentals ≤100 days exempt (§ 15B(9)).

Statute citations

G.L. c. 186, § 15B (1)(b)-(e), (2), (3), (4), (5), (6), (7), (8), (9) Official source

How this record was verified: Direct read of statute text on the official Massachusetts General Court site (malegislature.gov): G.L. c. 186, § 15B read in full (current text including the St. 2025, c. 9, §§ 54-55 amendments effective 2025-08-01), c. 186, § 12 read in full, c. 186 chapter index and c. 40P location confirmed on malegislature.gov, cross-checked against the Mass.gov official law-library pages on security deposits and landlord-tenant law (which also confirm c. 40P's continued force and the 2025 broker-fee change to c. 112, § 87DDD1/2).