The rules in this post are statutory and current as of August 25, 2026. Statutes move slowly, so this material holds for roughly 12 months. Review by August 2027.
One week from today, thousands of leases across Greater Boston start on the same morning, and a large share of the money that changes hands on September 1 is regulated down to the receipt. This post covers exactly what a landlord in Watertown, Waltham, or any Massachusetts town can collect at move-in, the deposit rules that carry triple damages, and who pays the broker fee now.
- Massachusetts law caps what a landlord can require at or before move-in at four items: first month's rent, last month's rent, a security deposit no larger than one month's rent, and the purchase and installation cost of a new lock and key, under M.G.L. c. 186, Section 15B.
- A Massachusetts security deposit must sit in a separate interest-bearing account at a bank in the state, and the tenant must receive a receipt naming the bank, its location, the amount, and the account number within 30 days (Mass.gov summary of Section 15B).
- A landlord who mishandles a security deposit can owe three times the deposit plus 5 percent interest, court costs, and attorney's fees (MassLegalHelp landlord guide, updated May 2025).
- Since August 1, 2025, only the party who engaged a rental broker pays that broker's fee in Massachusetts, and state officials warned in May 2026 that charging tenants a fee they did not agree to is illegal (Mass.gov, May 21, 2026).
- A Massachusetts lease cannot impose a late fee or interest until rent is 30 days overdue, under Section 15B(1)(c) of the same statute.
What Can a Landlord Legally Collect at a September 1 Move-In?
Four things, and only four: first month's rent, last month's rent, a security deposit up to one month's rent, and the cost of buying and installing a new lock and key. That list comes straight from Section 15B, and it is exhaustive. Anything else you collect at or before move-in is illegal, no matter what the lease says or what the tenant agreed to.
That kills a lot of charges landlords borrow from other states. Pet deposits and pet fees at move-in are out. Application fees are out. Move-in fees, cleaning fees, elevator fees, and holding deposits that do not convert into one of the four legal items are out. A tenant who signs a lease with an illegal fee in it has not waived anything, because the statute does not allow waiver.
The late fee rule surprises owners too. A Massachusetts lease cannot charge any late penalty or interest until the rent is a full 30 days overdue. For a September 1 lease, that means an October 1 payment that lands on October 15 has not yet triggered a legal late fee.
Collecting first and last at signing is standard practice across the September 1 market in Watertown and Waltham, and it is fully legal. The compliance burden starts when you take the third item, the security deposit, which is where most of the statute's teeth live.
Why the Security Deposit Is the Most Dangerous Dollar a Landlord Holds
Because the penalty for handling it wrong is three times the deposit plus interest, court costs, and attorney's fees, and the compliance checklist is longer than most self-managing landlords expect. Section 15B(7) makes treble damages mandatory for the listed violations, not something a judge weighs. On a $3,000 deposit, that is a $9,000 exposure before the legal bills.
The checklist runs like this. The deposit goes into a separate interest-bearing account at a Massachusetts bank, never your operating account. The tenant gets a receipt when they hand you the money, and a second receipt within 30 days naming the bank, its location, the amount, and the account number.
You also provide a statement of condition when you take the deposit or within 10 days of the tenancy starting, whichever is later, and the tenant has 15 days to send back corrections. Interest is due every year, at 5 percent or the actual bank rate if lower.
Miss the banking or receipt rules and the tenant can demand the entire deposit back immediately and still stay in the unit. Deduct for damage at move-out without a sworn, itemized list backed by bills or estimates within 30 days, and you can forfeit the right to deduct at all.
This is why a meaningful share of the landlords we lease for in Watertown and Waltham skip the deposit entirely and collect first and last only. That is a legitimate strategy, not a loophole. First and last month's rent carry an annual interest obligation and a receipt requirement, but none of the separate account mechanics and none of the treble damages exposure that follow the deposit itself.
Who Pays the Broker Fee for a September 1 Lease Now?
The party who engaged the broker pays the fee. That has been Massachusetts law since August 1, 2025, so this is the second September 1 cycle running under it. If you as the owner listed the unit with an agent, that fee is yours. A tenant owes a fee only to an agent the tenant hired, and the state reiterated in May 2026 that pushing the fee onto renters risks license discipline.
For owners in Waltham and Watertown, the practical question is pricing. The fee did not disappear, it moved, and owners are deciding listing by listing whether to absorb it or reflect it in rent. Rent level is not regulated in Massachusetts, so building your costs into the asking rent is legal. Collecting a side fee from the tenant to cover your agent is not.
What we tell our own landlords is to treat the fee as a marketing cost and judge it against vacancy. One extra vacant month on a $3,000 unit costs more than most fee arrangements, so the math usually favors whatever gets the unit leased fastest, not whatever shaves the fee.
The Week After Move-In, Two Clocks Are Already Running
The moment a September 1 tenant hands you a deposit, the 10-day statement of condition clock and the 30-day bank receipt clock both start. Those two documents are the ones we see self-managing landlords miss most often, because move-in week is chaos and nothing feels urgent until a move-out dispute two years later.
Our own practice at PH Realty Group is to document the unit's condition with dated photos before keys change hands on every lease we run, whether or not the owner takes a deposit. The statement of condition is only legally required when a deposit is taken, but the photo record is what settles arguments either way.
If you collected last month's rent, note the date and the amount on a receipt that says what it is, because that prepayment earns interest annually just like a deposit. Put a recurring reminder on the lease anniversary. Interest checks are small, and skipping them is the kind of clean, provable violation that turns a routine move-out into a demand letter.
If you own rental property in Watertown, Waltham, or the surrounding towns and you would rather have the compliance handled, the leasing side of this is exactly what PH Realty Group does all day. Reach out before your next vacancy and we will run the turnover, the paperwork, and the pricing conversation with you.
Frequently Asked Questions About Massachusetts Move-In Rules
How much can a landlord charge for a security deposit in Massachusetts?
A Massachusetts security deposit is capped at one month's rent under M.G.L. c. 186, Section 15B, and a landlord cannot require more at any point in the tenancy.
Can a Massachusetts landlord charge a pet deposit, application fee, or move-in fee?
No. Massachusetts law limits move-in charges to first month's rent, last month's rent, a security deposit of up to one month, and the cost of a new lock and key, so pet deposits, application fees, and move-in fees are illegal for landlords to collect.
Who pays the rental broker fee in Massachusetts in 2026?
Since August 1, 2025, Massachusetts law requires the party who engaged the broker to pay the broker's fee, so a tenant only owes a fee to an agent the tenant personally hired.
When must a Massachusetts landlord return a security deposit?
A Massachusetts landlord must return the security deposit, minus lawful deductions supported by a sworn itemized list, within 30 days after the tenancy ends.
What happens if a landlord does not put the deposit in a separate Massachusetts bank account?
A tenant whose deposit is not held in a separate interest-bearing Massachusetts bank account can demand its immediate return, and the violation can expose the landlord to three times the deposit plus interest, court costs, and attorney's fees.
Do Massachusetts landlords owe interest on last month's rent?
Yes. Last month's rent collected in advance earns interest at 5 percent per year, or the actual bank rate if lower, and the landlord must pay or credit it to the tenant each year of the tenancy.
