Optional Massachusetts auto insurance coverages: Parts 5 through 12 explained.

The Massachusetts auto policy: compulsory Parts vs. optional Parts

Massachusetts builds its auto policy out of numbered Parts. By law you must buy four compulsory coverages in at least the minimum amounts. Those four protect other people and provide some protection for you: Bodily Injury to Others at $25,000 per person and $50,000 per accident, Bodily Injury Caused by an Uninsured Auto at the same 25/50, Damage to Someone Else’s Property at $30,000 per accident, and Personal Injury Protection benefits up to $8,000 per person per accident. Those minimum amounts increased as of July 1, 2025.

Here is the catch. The compulsory coverages pay when you injure someone or damage another person’s property, and they pay some of your own medical costs through PIP. They do not pay to repair your own vehicle, and your compulsory bodily injury protection only applies to accidents inside Massachusetts. That is why the policy also offers optional coverages, Parts 5 through 12, which every insurer is required to make available. Accidents often cause damage that exceeds the required minimums, so many drivers add optional coverage or higher limits. For the fuller walkthrough of how the compulsory side works, see our guide on how car insurance works in Massachusetts.

The optional Parts are: Part 5 Optional Bodily Injury to Others, Part 6 Medical Payments, Part 7 Collision, Part 8 Limited Collision, Part 9 Comprehensive, Part 10 Substitute Transportation, Part 11 Towing and Labor, and Part 12 Bodily Injury Caused by an Underinsured Auto.

Part 5 optional bodily injury and Part 12 underinsured motorist

Two optional Parts sit on the liability side of the policy. Part 5 does two things. First, it extends your bodily injury coverage outside Massachusetts. Because Part 1 only applies to in-state accidents, you must buy Part 5 even at the minimum limit to be covered when you drive to other states. Buy it, and your coverage follows you everywhere in the U.S. Second, Part 5 lets you raise your bodily injury limits above the compulsory floor, for example to 40/90, meaning $40,000 for one person and $90,000 for everyone hurt in one accident, and it covers passengers in your car. On policies assigned through the MAIP, insurers must make Part 5 limits available up to 250/500 on request.

Part 12 protects you against a driver who is at fault but does not carry enough insurance to cover your injuries. The basic limits are $25,000 per person and $50,000 per accident. Two mechanics matter. Part 12 is excess, so anything you collect from the at-fault driver’s bodily injury coverage is subtracted from your Part 12 limit. And your Part 12 limit cannot exceed your Part 5 limit, or your Part 1 limit if you did not buy Part 5. In practice, raising Part 5 is often what unlocks meaningful underinsured protection. On MAIP-assigned policies, Part 12 is also available up to 250/500.

Collision vs. comprehensive vs. limited collision (Parts 7, 8, 9)

These are the coverages that pay for your own car, and the choice between them is the one drivers ask about most.

Collision, Part 7, pays for damage to your vehicle when it collides with another vehicle or an object such as a guardrail. It applies regardless of who is at fault, and it can also help pay certain towing and temporary storage charges tied to a covered accident, subject to policy limits.

Comprehensive, Part 9, pays for damage from events other than a collision: theft, vandalism, fire, falling objects, flooding, falling branches, and contact with animals, plus glass damage not related to a collision. If your car is stolen, comprehensive pays to repair it if it is recovered, or pays its actual cash value if it is not.

Limited Collision, Part 8, is a narrower option that may cover collision damage only in certain situations. Drivers usually choose either full collision or limited collision, not both.

All three are written on an actual cash value basis, up to a maximum limit of loss of $175,000 per vehicle. Actual cash value matters. On an older car, the most these coverages pay is what the car was worth at the time of loss, not what a new one costs.

Deductibles and how to set them

Parts 7, 8, and 9 carry a deductible, the amount you pay out of pocket before coverage applies. The basic deductible is $500 unless you choose a different amount, and that $500 figure applies to fire, theft, and combined additional coverage as well. A $300 deductible is available subject to insurer underwriting, and higher deductibles are available too. Choosing a higher deductible lowers your premium, because you agree to absorb more of each loss.

Setting the deductible is a straightforward trade. A higher deductible saves premium every year but costs you more the day you file a claim. Match it to the cash you could comfortably put toward a repair without straining. Note also that insurers must charge an extra-risk rate, or refuse collision and comprehensive coverage entirely, under certain circumstances required by law, so an older vehicle or a rough driving record can affect availability and price.

Part 6 medical payments and the smaller optional Parts

Part 6, Medical Payments or MedPay, has a basic limit of $5,000 per person, with higher limits available. It is excess over Personal Injury Protection, so it picks up after PIP. Insurers must offer at least $5,000. If you already carry good health insurance, weigh carefully whether you need much MedPay, since there is overlap. Our guide on PIP in Massachusetts explains how the primary layer of your medical coverage works before MedPay comes in.

Part 10, Substitute Transportation, pays for loss of use of your vehicle after an accident or loss, for example a rental car while your car is repaired following a collision or comprehensive claim. If losing your car for a week would leave you stranded, this is a low-cost gap to close.

Part 11, Towing and Labor, pays up to $50 or up to $100 for towing and labor for each disablement, and it is available only for private passenger vehicles and motorcycles. If you already belong to a Motor Club that includes towing, you may not need Part 11 at all.

How to decide which optional coverages to buy

Start with your car. If it is worth repairing or replacing, collision and comprehensive earn their premium; if you finance or lease, the lender will require both. If the car is old and near the end of its life, weigh the annual cost against its actual cash value, since that value is the ceiling on any payout. Then set the deductible to a number you could pay tomorrow.

Next, look at your driving. If you ever leave Massachusetts, Part 5 is not optional in any practical sense, because without it your bodily injury coverage stops at the border. Raising Part 5 also raises the ceiling on Part 12, so drivers who want real underinsured protection usually address both together. Higher liability limits are also the foundation an umbrella policy sits on if you want protection beyond the auto policy.

Finally, trim the overlaps. Skip or reduce MedPay if your health plan is strong, and skip Part 11 if your Motor Club already tows. We shop these choices across many carriers and place the policy that fits, and you can start with our auto quote page.