Massachusetts Used Car Lemon Law: Dealer Warranty and 7-Day Rule

Massachusetts gives used car buyers two separate protections. If you buy from a dealer for at least $700 and the car has under 125,000 miles, Chapter 90, section 7N1/4 requires a written warranty of 90 days or 3,750 miles, 60 days or 2,500 miles, or 30 days or 1,250 miles depending on the odometer, and three failed repairs or more than 10 business days in the shop gets you a buyback. Separately, section 7N lets you void a dealer or private sale if the car fails the state inspection within 7 days and repairs would cost more than 10% of the price.

I read both statutes on malegislature.gov and the state's consumer guide on the morning of October 17, 2026. Mass.gov blocks our link checker, so those pages are named below without links. This is general information, not legal advice. The deadlines are short, so if a dealer stalls, call a lawyer or the Office of Consumer Affairs at (617) 973-8700 early.

Who the dealer warranty covers

Under M.G.L. c. 90, s. 7N1/4, a dealer is anyone who sold more than three used vehicles in the previous 12 months, licensed or not, as the state's Guide to Used Vehicle Warranty Law also says. Banks and government sellers are excluded, and so are lease buyouts and an employer selling to an employee. Motorcycles, motor homes, off-road vehicles and cars used mainly for business don't qualify. Sales under $700 are exempt under subsection (7).

Mileage at the time of sale sets the term. Under 40,000 miles you get 90 days or 3,750 miles, 40,000 to 79,999 gets 60 days or 2,500 miles, and 80,000 to 124,999 gets 30 days or 1,250 miles, whichever comes first. If the true mileage isn't known, the statute switches to age: three years old or less gets the longest term, more than three but under six gets the middle one, and six or older gets the shortest.

The warranty covers parts and labor for any defect that impairs the car's safety or use. Cosmetic problems are out, and you can be charged no more than $100 total toward covered repairs during the warranty. You can't waive it, and if the paperwork is missing or wrong, the guide says your term doesn't start until you get a correct copy. An "as is" box on the window sticker doesn't change that: the FTC's Buyers Guide rule, 16 CFR 455.2, says state law that limits as-is sales overrides it.

Repairs, the 10-day count and the buyback

The statute says the dealer must accept the car immediately when you present it, and gives you up to five business days after the warranty expires to bring it back for a defect. The state guide puts it as accepting the car within three business days of a phone or written request. The dealer pays towing up to 30 miles from a breakdown. Every repair also carries its own 30 days of coverage from the day it's finished.

If the dealer fails to fix the same defect in three attempts, or the car is out of service more than a cumulative 10 business days, the dealer has to take it back and refund the repurchase price. The guide describes that as 11 business days and says any combination of defects counts. Days waiting on a part the dealer ordered promptly don't count, but that pause can't run past 21 days. The refund includes the price, fees, finance charges and your $100 repair payments, minus 15 cents for every mile you drove. Towing and up to $15 a day for a rental after day two of a breakdown can be added.

The guide adds two warnings. If the dealer offers a full refund and you say no, you lose further warranty repairs. And if you owe more on the loan than the award, you cover the gap; the guide warns about negative equity. Sales tax and excise aren't part of the refund, so ask your town hall about an excise abatement and the Department of Revenue about the sales tax.

Arbitration: six months, $300, virtual hearing

If the dealer won't buy the car back, you can ask the Office of Consumer Affairs and Business Regulation for state-certified arbitration. The statute requires the request within six months of delivery, and the agency's Apply for Lemon Law Arbitration page says applying is free, but you pay $300 to the arbitrator once a hearing is scheduled, which goes into the award if you win. Hearings are held on Microsoft Teams. The finding is due within 45 days of your request, and a dealer that loses has 21 days to pay or appeal with a bond. If it does neither, the statute fines it $50 a day, capped at $500. You can also sue, but you have two years from delivery.

The 7-day inspection rule, for private sales too

Section 7N works regardless of any warranty disclaimer and covers cars bought for personal or family use. Get the car inspected within seven days of the sale. If it fails, the defects weren't caused by your driving or a post-sale crash, and repairs to pass would cost more than 10% of the price, you can void the sale. You must notify the seller within 14 days of the sale, return the car and hand over a signed statement from the inspection station with the reasons and a repair estimate. The seller can instead fix it at its own cost if you both agree in writing. On a $6,000 private sale, the bar is $600 in repairs.

Private sellers also have a disclosure duty under 7N1/4(8): they have to tell you about known defects that impair safety or substantially impair use, and if they don't, you can rescind within 30 days. See our Massachusetts private-sale title transfer guide for paperwork, and the pre-purchase inspection cost post explains why paying a shop before you buy beats arguing after.

What a history report adds

None of these laws tell you what happened to the car before you met it. A CARFAX can list flood or lemon titles, last reported mileage and possible rollbacks, according to CARFAX's report page, and our lemon buyback on CARFAX post shows what a prior buyback looks like. If it shows a crash the dealer never mentioned, read what to do when a dealer didn't disclose an accident. CarVins is a licensed CARFAX and AutoCheck reseller, unaffiliated with either. In mid October 2026 one report runs about $5.50 as a guest or $4.50 for members, near $6.75 for both, versus $39.99 to $44.99 retail; check the cart.

Sources

• M.G.L. c. 90, s. 7N1/4
• M.G.L. c. 90, s. 7N
• CARFAX vehicle history reports
• Mass.gov: Guide to Used Vehicle Warranty Law and Apply for Lemon Law Arbitration (read Oct. 17, 2026; not linked)