Massachusetts security deposit rules.
The Massachusetts rules for residential security deposits in plain English: how much can be charged, how fast it comes back, whether interest is owed, and what catches operators out.
Last reviewed · Statute: Mass. Gen. Laws ch. 186, § 15B · Not legal advice
How much can be charged
Capped at one month of rent. Last month’s rent and a separate key-deposit are also allowed under specific rules.
When it has to come back
30 days from termination, with itemised deductions and supporting receipts within the same window.
Interest
5% per year, or the lesser amount the bank actually paid on the account. Paid annually within 30 days of each anniversary, or within 30 days of termination.
Where the money has to sit
Deposits must be held in a separate, interest-bearing account at a Massachusetts-located institution.
What catches operators out
- Massachusetts deposit law is famously unforgiving — small procedural mistakes (missing receipt, late interest, wrong account) all forfeit the deduction right and trigger triple damages.
- Required Statement of Condition must be delivered within 10 days of move-in.
What this looks like with Standby in Massachusetts.
When a resident takes a Standby certificate there is no cash deposit to hold, so the cap, the return deadline and the interest rules above have nothing to attach to. You are covered up to the full deposit and draw on it when you need to.
When a resident pays cash instead, Standby handles that deposit under your lease and Massachusetts law, so your team is not tracking interest and return deadlines by hand.
This page summarises the most common single-family and multifamily residential rule in Massachusetts. Furnished units, senior leases, mobile-home tenancies and short-term rentals can differ, and city ordinances may override the state default. Check the statute before relying on a figure for a specific lease.