It must sit in a separate bank account and come back within 30 days.
From the Massachusetts Legislature, read Oct 1, 2026.Show the law
“a security deposit equal to the first month's rent provided that such security deposit is deposited as required by subsection (3) and that the tenant is given the statement of condition as required by subsection (2)”
G.L. c. 186, § 15B · malegislature.gov · found word for word in the source
Who can help
Ask the Boston Office of Housing StabilityFree counselors explain your options, by phone or in person.Boston Office of Housing Stability
Get free legal helpThey can help you ask for it, or go to small claims court.MassLegalHelp
State law applies here too. Where both cover a rental, the stricter city rule usually wins; each rule below says so.
Massachusetts lawIn force
Massachusetts security deposit law
How big can the deposit be?
Max 1 month's rent.
It must sit in a separate bank account and come back within 30 days.
Who it covers
Exemptions: Vacation or recreational tenancies of 100 days or less.
In force since
Aug 1, 2025
The law, word for word
“a security deposit equal to the first month's rent provided that such security deposit is deposited as required by subsection (3) and that the tenant is given the statement of condition as required by subsection (2)”