10.2 Part A Liability and Part B Medical Payments

Key Takeaways

  • Part A pays bodily injury and property damage for which an insured is legally responsible; typical PAP defense costs are in addition to the limit of liability until that limit is exhausted by judgments or settlements.
  • Split-limit notation such as 25/50/25 illustrates BI per person / BI per accident / PD per accident; those numbers are state-varying and are not a national legal minimum.
  • Out-of-state coverage raises Part A to at least the other state's compulsory amounts for that accident; financial-responsibility clauses make the policy certify as proof of FR to the extent required.
  • Part A exclusions include intentional injury, public or livery (share-the-expense carpools are usually excepted; ride-share generally needs an endorsement), vehicles with fewer than four wheels, and vehicles furnished for regular use such as a company car.
  • Part B medical payments is first-party and no-fault as to the occupant; you and family members are also covered as pedestrians struck by a motor vehicle designed mainly for public-road use, and occupying means in, upon, getting in, on, out, or off.
Last updated: August 2026

10.2 Part A Liability and Part B Medical Payments

Quick Answer: Part A pays bodily injury and property damage for which an insured is legally responsible, and a typical PAP pays defense in addition to the limit. Limits may be split (illustrated as 25/50/25—BI per person / BI per accident / PD) or a combined single limit (CSL). Those numbers are state-varying, not a U.S. legal minimum. Part B Medical Payments is first-party and no-fault as to the occupant. A company car furnished for regular use is a Part A trap; borrowing a neighbor’s car is usually excess on the borrower’s PAP.

AINS 102 will not ask you to define liability in the abstract. It will give you an accident with two injured people, a split-limit dec page, a rideshare weekend, or a sedan the employer issued. Your job is to name the grant, the insured, the limit that actually pays, and the exclusion that may kill the file.

Part A: the third-party grant

Part A agrees to pay damages for BI and PD for which an insured becomes legally responsible because of an auto accident. Legal responsibility is the point. A courtesy payment to a friend is not the grant. A judgment, a settlement the insurer defends, or a statutory obligation the form recognizes is the grant.

Defense. The typical ISO PAP promises to settle or defend and treats investigation and defense costs as in addition to the limit of liability. Paying a lawyer does not erode the $50,000 BI cap the way a CGL defense-inside-limits endorsement would. When the limit is exhausted by judgments or settlements, the duty to defend ends. Supplementary payments (bail bonds up to a modest stated amount, appeal bonds, post-judgment interest, loss of earnings for attendance at hearings at a stated daily cap) sit beside that defense promise. They are not a second liability limit.

Split limits versus combined single limit

Split limits are written as three numbers. The illustration 25/50/25 means:

NumberMeaning
25$25,000 BI per person
50$50,000 BI per accident (all persons combined)
25$25,000 PD per accident

If one person has $40,000 of BI and a second has $20,000, and PD is $12,000, Part A pays $25,000 on the first person (per-person cap), $20,000 on the second (within the leftover per-accident BI), and $12,000 PD—$57,000, not $72,000. The per-accident BI cap of $50,000 would have cut a larger two-person total.

25/50/25 is a teaching illustration, not a national legal minimum. Compulsory auto and financial responsibility (FR) limits are set by each state and change. Some states sit below that illustration; many sit above it. Never tell an exam reader that every U.S. driver “must carry 25/50/25.” Read the dec page and, when the stem mentions another state, read that state’s compulsory amounts.

A combined single limit is one dollar amount for all BI and PD in one accident. A $100,000 CSL can pay one person’s $90,000 BI and $10,000 PD, or several people, until the single pot is gone. Split-limit math and CSL math are not interchangeable.

Out-of-state coverage and financial responsibility

If an accident occurs in another state or province that requires higher compulsory liability limits or a different kind of coverage (for example, a no-fault add-on the PAP does not otherwise provide), Part A’s out-of-state coverage clause typically raises this policy to at least those compulsory amounts for that accident. The insured does not have to call the CSR from the rest-stop to “activate” it.

The financial responsibility clause says the policy conforms to the FR law of the state to the extent required and can be certified as proof of FR. Certification can impose extra obligations (no inner limits that undercut the certified amount). It is not a promise that the PAP matches every residual-market or no-fault statute in the country without endorsements.

Part A exclusions that AINS actually tests

Walk exclusions only after you have a grant and an insured.

  • Intentional BI or PD by that insured. Road rage that is a deliberate ramming is not an accident the grant was built to finance.
  • Public or livery conveyance. Using the auto as a taxi or to haul paying strangers is excluded. A share-the-expense carpool (coworkers splitting gas and parking, no fare-profit business) is usually excepted from that exclusion. Uber/Lyft and other transportation network company (TNC) use is not a carpool. Period 1 (app on, waiting for a match) is the famous PAP gap; the TNC’s commercial policy may respond in later periods. The household typically needs a ride-share / TNC endorsement if that exposure exists.
  • Fewer than four wheels or vehicles designed mainly for off-road use (with narrow exceptions such as a medical emergency, a trailer, or a non-owned golf cart). Motorcycles do not sneak into Part A because someone has a PAP.
  • Vehicles furnished or available for regular use of the named insured, other than your covered auto. The company car the employer issues for weekday commuting is the trap. The employee’s PAP is not a free excess policy on that sedan. Extended non-owned coverage is how many households buy that exposure back. A neighbor’s car borrowed twice a year is not “regular use.” A coworker’s car used every workday may be.
  • Auto-business use (selling, repairing, servicing, storing, parking autos) except in limited “you / family / partner / employee” situations involving your covered auto; racing; nuclear and war; care, custody, or control of property (other than a residence or private garage) that the insured damages.

Workplace walk: an insured with a PAP and no extended non-owned endorsement totals a fleet sedan the employer furnished. Part A on the personal policy is the wrong well to drink from. The employer’s business auto form is the starting point.

Part B Medical Payments

Part B pays reasonable expenses for necessary medical and funeral services because of bodily injury caused by an accident and sustained by an insured. It is first-party. You do not have to prove the insured was legally liable. It is no-fault as to the occupant in the sense that occupancy-plus-accident triggers the grant, subject to exclusions and to other-insurance rules. Limits are typically per person. Many editions also impose a time window (often three years from the accident) for incurred expenses.

Who is an insured for Part B:

  • You and any family member while occupying a motor vehicle designed mainly for use on public roads, or as a pedestrian when struck by such a vehicle (or by a trailer of one).
  • Any other person while occupying your covered auto.

A guest in the listed Honda can have Part B. A guest in a borrowed neighbor car generally cannot take Part B from your PAP; that occupant looks to the owner’s Part B or to health insurance. You and a family member can take Part B from your PAP while occupying that neighbor car, unless an exclusion (regular use, fewer than four wheels, no reasonable belief of permission) applies.

Occupying is defined: in, upon, getting in, on, out, or off. Shutting a door, sliding out of a seat, or being on the auto can still be occupying. Standing a block away after parking is not.

Pedestrian coverage is easy to miss. A named insured walking a dog who is struck by a city bus is a Part B insured on the family PAP. The bus does not have to be a covered auto. The striking vehicle does have to be a motor vehicle designed for public-road use—not a claim that a falling bicycle in a park is Part B.

Part B exclusions overlap Part A in places (public/livery, fewer than four wheels, furnished-for-regular-use vehicles, racing, occupying without reasonable belief of permission) and add others (vehicles used as a residence, workers compensation, uninsured vehicles the insured owns).

Borrowing the neighbor’s car

Name the auto first. The neighbor’s sedan is not your covered auto. While you drive it with permission and it is not furnished for your regular use, you (and typically a family member) are a Part A insured on your PAP for that non-owned auto. The neighbor is an insured on the neighbor’s PAP, which is usually primary. Your Part A is typically excess (Part F other-insurance, taught in 10.4). Passengers in the neighbor’s car are not additional named insureds on your policy. That single walk—covered auto versus non-owned, who is an insured, primary versus excess—is the Assignment 2 liability item.

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Part A liability versus Part B medical payments
Test Your Knowledge

An accident causes $40,000 of BI to one person, $20,000 of BI to a second person, and $12,000 of PD. The PAP shows split limits of 25/50/25. Ignoring defense costs, how does Part A typically respond?

A
B
C
D
Test Your Knowledge

The named insured borrows a neighbor's personal auto, which is not furnished for regular use, and injures a pedestrian. The neighbor's PAP is in force. Who is an insured on the named insured's PAP for this Part A claim?

A
B
C
D
Test Your Knowledge

Which use of a covered auto is most likely still within Part A without a transportation-network or livery endorsement?

A
B
C
D
Test Your Knowledge

An employer furnishes a sedan that the named insured drives every workday. After hours, a family member walking a dog is struck by a city bus. The family PAP has no extended non-owned endorsement. Which pairing is most accurate?

A
B
C
D