Tools · Security Deposit
Massachusetts Security Deposit Calculator (2026)
Enter your rent and move-out date to see the most a Massachusetts landlord can charge and the exact date your deposit is due back — up to 1 month of rent, returned 30 days after the tenancy ends.
Massachusetts security deposit calculator
These are the Massachusetts figures applied to what you entered — a plain summary of the rule and the dates, not a determination that anyone did or did not comply.
- Maximum deposit
- $2,000 · 1 month rent
- Monthly rent
- $2,000
- Move-out date
- Not entered
- Return deadline (30 days)
- 30 days
Plain-language summary, not legal advice.
Informational only, not legal advice. Security-deposit rules carry exceptions (lease type, small landlords, city ordinances) this summary cannot weigh. See the full statute and exceptions on the Massachusetts security deposit reference, cited to M.G.L. c.186 §15B.
How Massachusetts security deposits work
Massachusetts has some of the strictest deposit paperwork rules in the country, and landlords who slip up pay dearly. The deposit is capped at one month's rent, must sit in a separate interest-bearing Massachusetts bank account beyond the reach of creditors, and earns you 5% a year. But the treble-damages hammer is narrower than many tenants assume: under §15B(7) it applies to three specific failures — not accounting properly, not transferring the deposit to a new owner, or not returning it within 30 days — with a separate treble penalty under §15B(2)(a) for failing to pay the required interest. Botching the sworn damage list forfeits the right to withhold, but isn't automatically triple damages.
This calculator shows the Massachusetts figures applied to your own rent and dates. It is informational only and not legal advice — exceptions this summary cannot weigh may apply. For the full rules, penalties, and citations, see the Massachusetts security deposit reference.
Security deposit calculators for other states
Same tool, each with its own cap and return deadline.