Renting out a room in Massachusetts makes you a landlord under state law, even though you still live in the home. That status brings real obligations: habitability standards, strict deposit rules, fair housing law, lead paint disclosures, insurance adjustments, and tax reporting. Get the setup right before anyone moves in, because Massachusetts enforces these rules aggressively and a security deposit mistake alone can cost you triple damages.
What You Can Legally Charge at Move-In
Massachusetts limits what you can collect before a tenant takes the room. Under M.G.L. c. 186, §15B, only four charges are allowed:
- First month’s rent
- Last month’s rent, at the same rate as the first month
- A security deposit no greater than one month’s rent
- The actual cost of a new lock and key
That is the full list. Application fees, pet fees, move-in fees, cleaning fees, and holding deposits are all illegal here. Charging any of them puts you in violation on day one.
Handling a Security Deposit
If you take a security deposit, it has to go into a separate interest-bearing bank account in Massachusetts, never mingled with your own money. Within 30 days of receiving it, give the tenant a written receipt showing the bank’s name, address, and the account number. Within 10 days of the tenancy starting, give the tenant a detailed Statement of Condition describing the room. The tenant earns whatever interest the bank pays; if you don’t put the money in a bank at all, you owe five percent annually.
Procedure matters as much as the money. A court can order you to return the full deposit and pay the tenant up to three times that amount, plus attorney’s fees. This is one of the most litigated issues in Massachusetts landlord-tenant law. If you collect last month’s rent in advance, it also has to sit in an interest-bearing account, with the interest belonging to the tenant.
Making the Room Habitable
The Massachusetts State Sanitary Code, 105 CMR 410, sets minimum standards for any room you rent. Local boards of health enforce it, and a tenant complaint can trigger an inspection. Falling short gives the tenant grounds to withhold rent or break the lease.
Size, Light, and a Lock
A sleeping room for one person needs at least 70 square feet of floor space. For two people sharing, it’s at least 50 square feet per person. The room must have at least one window for natural light and ventilation, and the door needs a working lock so the tenant can secure their private space.
Heat, Plumbing, and Kitchen
From September 15 through June 15, every habitable room and bathroom has to be kept at 68°F between 7 a.m. and 11 p.m., and at least 64°F overnight, and no higher than 78°F during heating season. If the lease shifts fuel costs to the tenant, that arrangement has to be in writing.
The tenant needs access to a bathroom with a toilet, sink, and bathtub or shower. If the kitchen is shared, it must have a working sink, stove, and oven, and keeping it in good repair is on you.
Smoke and Carbon Monoxide Alarms
Working smoke detectors are mandatory in every Massachusetts residence. Carbon monoxide alarms are required wherever there is fossil-fuel-burning equipment or an attached enclosed garage. Test monthly, change batteries twice a year, and replace the units themselves every ten years, or sooner if the manufacturer says so.
Lead Paint: Extra Steps if the House Is Pre-1978
If your home was built before 1978, you have both federal and Massachusetts lead paint duties, and the state’s go further.
Federal law requires you to give the prospective tenant the EPA pamphlet “Protect Your Family From Lead in Your Home,” disclose any known lead paint or hazards, share any existing inspection reports, and include a lead warning statement in the lease. Keep signed copies for at least three years.
Massachusetts then adds its own layer. Before the tenant signs, provide two copies of the state’s Tenant Notification and Tenant Certification Form, one for each of you to sign and keep. Hand over any existing lead inspection reports and any Letter of Compliance or Letter of Interim Control for the unit.
The biggest Massachusetts rule: if a child under six will live in the home, you must de-lead or bring the property into “lead-safe” condition. You can’t refuse to rent to families with young children to dodge this, and you can’t pass the cost to the tenant. You may delay the start of the tenancy by up to 30 days to begin compliance, but the responsibility is yours. A violation can trigger triple damages under the state consumer protection statute.
Fair Housing When You Share Your Home
Massachusetts prohibits discrimination based on race, color, religion, national origin, sex, gender identity, sexual orientation, age, ancestry, marital status, disability, familial status, military service, and receipt of public assistance or housing subsidies. The rules reach advertising, screening, and lease terms.
You may have heard about the federal “Mrs. Murphy” exemption for owner-occupied buildings with four or fewer units. Massachusetts has a much narrower version: it exempts only the rental of a unit in an owner-occupied two-family dwelling when no broker is involved. Renting a room inside your single-family home does not clearly fall under that exemption, so treat every fair housing requirement as applying to you.
Discriminatory advertising is illegal even where an exemption would otherwise apply. Ads saying “No children” or “Females only” are out. Keep your listing focused on the room, the rent, and practical details like parking or shared spaces.
Service and Emotional Support Animals
You can’t refuse a tenant’s request to keep a service animal or emotional support animal, and you can’t charge a pet deposit or pet fee for one. Assistance animals aren’t pets under fair housing law. If the disability and the need for the animal aren’t obvious, you can ask for documentation from the tenant’s medical provider, but you can’t demand specific forms or certifications, and you can’t require letters from online-only services. Narrow exemptions exist for some owner-occupied two-family homes and single-family rentals without a broker or public advertising, but they rarely apply in practice.
Screening Applicants Without Creating Liability
You can ask about income, employment history, and references from prior landlords. You can run a credit check or criminal background check with the applicant’s written consent. You cannot charge any application fee.
If you turn an applicant down based wholly or partly on a credit report or background check, federal law requires an adverse action notice. It has to name the reporting agency, state that the agency didn’t make the decision, and tell the applicant how to dispute the report’s accuracy and get a free copy within 60 days. If a credit score played a role, you must also share the score, the scoring range, and the key factors that hurt it.
Use the same criteria for every applicant. Different standards for different people, outside legitimate financial and rental-history factors, create fair housing liability.
Putting the Agreement in Writing
Write the arrangement down. A workable rental agreement for a room covers monthly rent and due date, whether the tenancy is month-to-month or fixed-term, which areas are shared and which are private, who pays for utilities, and house rules on guests, noise, and common spaces. Shared-home disputes escalate fast, and documented terms head most of them off.
For pre-1978 homes, the lead warning statement and disclosure documents have to be attached to or incorporated into the lease. Include language on the room’s condition that lines up with the Statement of Condition you deliver at move-in.
Call Your Insurance Company First
A standard homeowners policy assumes an owner-occupied home with no paying tenants. Once rent is coming in, your insurer may deny a claim tied to the tenant or their guests, treating the arrangement as a business activity. Some policies exclude paying guests outright; others simply don’t contemplate the setup.
Call your insurer before the tenant moves in and describe what you’re doing. For a single rented room in a home you still live in, an endorsement on your existing policy may be enough, rather than a full landlord policy. The cost is modest next to the risk of an uncovered liability claim. Encourage the tenant to carry renter’s insurance for their own belongings and personal liability.
Reporting the Rent on Your Taxes
Rent you collect is taxable income. Report it on federal Schedule E, and on the Massachusetts Schedule E for state purposes.
You can deduct a proportional share of your housing expenses against that income: mortgage interest, property taxes, insurance, utilities, maintenance, and depreciation on the rental portion of the home. Allocate by number of rooms or by square footage, whichever fits your situation better. Expenses tied only to the rented room, like furniture bought for the tenant, are fully deductible against rental income.
Deductions can’t exceed the gross rental income from the room. If expenses are higher in a given year, the excess carries forward instead of offsetting your other income. That limit exists because you also live in the home and use it personally.
Entering the Room and Ending the Tenancy
Sharing a house doesn’t give you unlimited access to the tenant’s room. The sanitary code requires at least 48 hours’ written notice before entering for repairs. Your lease can allow entry to inspect or to show the room to prospective tenants or buyers, but spell that out in writing. You can enter without notice in a genuine emergency, like a burst pipe or fire, or if the room appears abandoned. During the last 30 days of the tenancy, you can enter to inspect for damage affecting the deposit return. Otherwise, the room is the tenant’s private space.
For a month-to-month tenancy, either side can end it with written notice equal to the interval between rent payments or 30 days, whichever is longer, with the notice set to expire at the end of a rental period. If the tenant stops paying, you can serve a 14-day notice to quit; if they haven’t received a similar notice in the past 12 months, they have 10 days from receipt to cure by paying what’s owed.
A notice to quit is not an eviction. If the tenant stays past the notice period, you have to file a summary process case in court. You cannot change the locks, shut off utilities, or move the tenant’s belongings out yourself. Self-help evictions are illegal and carry substantial liability, so plan on the court route from the start.