12.5 Commercial Auto Endorsements

Key Takeaways

  • ISO commercial auto endorsements (CA series) tailor the lean BACF; the exam tests what each adds, removes, or fixes.
  • Drive Other Car (CA 99 10) covers a named individual with no personal auto; Employees as Insureds (CA 99 33) protects the employee personally, which Symbol 9 alone does not.
  • Auto Loan/Lease Gap (CA 20 71) pays the ACV-to-loan-balance shortfall on a totaled financed auto, excluding rolled-over balances, finance charges, and overdue payments.
  • Rental Reimbursement, Towing and Labor, and Audio/Visual endorsements round out physical-damage needs.
  • Large commercial auto fleets are experience rated: modified premium = manual premium x mod, where a mod above 1.00 surcharges and below 1.00 credits the premium.
Last updated: June 2026

Why Endorsements Matter

The Business Auto Coverage Form is deliberately lean; carriers tailor it with ISO commercial auto endorsements (the CA series). The exam tests what each endorsement adds, removes, or fixes — and a few classic traps about which exposures are still uncovered.

Core Liability and Use Endorsements

EndorsementEffect
Drive Other Car (DOC) – Broadened Coverage for Named Individuals (CA 99 10)Gives a named individual (often an executive with no personal auto) PAP-like coverage when using autos the business does not own
Individual Named Insured (CA 99 17)Extends personal-auto-style coverage (including family members) when the named insured is an individual, not an entity
Employees as Insureds (CA 99 33)Makes employees insureds while using THEIR OWN autos in the named insured's business — adds protection Symbol 9 alone does not give the employee
Mobile Equipment (CA 20 15)Schedules mobile equipment as covered autos for liability
Hired Autos Specified as Covered Autos (CA 20 48)Treats described hired autos as owned for broader coverage

Trap: Symbol 9 covers the employer's vicarious liability for an employee's car; only CA 99 33 (Employees as Insureds) also protects the employee as an insured. Distinguish the two on the exam.

Physical Damage, Cargo, and Specialty Endorsements

EndorsementEffect
Rental Reimbursement (CA 99 23)Pays a daily/maximum amount for a substitute rental after a covered physical-damage loss
Auto Loan/Lease Gap (CA 20 71)Pays the difference between the auto's ACV and the unpaid loan/lease balance after a total loss
Towing and Labor (CA 99 03)Adds a per-disablement towing sublimit, usually for private passenger autos
Audio/Visual & Data Electronic Equipment (CA 99 60)Schedules added value of permanently installed electronics
Pollution Liability – Broadened Coverage (CA 99 48)Broadens narrow pollution coverage for autos carrying their own fuel/fluids
Motor Carrier endorsements (e.g., MCS-90, Trailer Interchange CA 23 17)Federal guarantee and trailer-of-others coverage

Worked Example: Loan/Lease Gap

A financed pickup is totaled. ACV at the time of loss is $24,000; the outstanding loan balance is $31,500; physical-damage deductible is $1,000.

  • Standard physical damage pays ACV minus deductible: $24,000 - $1,000 = $23,000.
  • The owner still owes $31,500 - $23,000 = $8,500 to the lender.
  • Auto Loan/Lease Gap (CA 20 71) pays that $8,500 shortfall (subject to its terms excluding overdue payments, carry-over balances, and certain fees), so the insured is not left owing on a destroyed vehicle.

Trap: Loan/Lease Gap excludes amounts rolled over from a prior loan, unpaid finance charges, and overdue payments — it does not bail out poor financing, only the legitimate ACV-to-balance gap.

Choosing the Right Endorsement

NeedEndorsement
Executive with no personal auto driving company/borrowed carsDrive Other Car (CA 99 10)
Protect the employee personally for using own car on businessEmployees as Insureds (CA 99 33)
Cover the gap on a totaled financed vehicleAuto Loan/Lease Gap (CA 20 71)
Provide a rental while a damaged auto is repairedRental Reimbursement (CA 99 23)
Cover trailers of others under interchange agreementsTrailer Interchange (CA 23 17)

Experience Modification Context

While experience rating is most prominent in workers compensation, large commercial auto fleets are also experience rated: an experience modification factor (mod) above 1.00 surcharges premium for worse-than-expected losses; below 1.00 credits it.

Worked example: A fleet with a manual premium of $80,000 and an experience mod of 1.15 pays $80,000 x 1.15 = $92,000. After a clean year the mod drops to 0.90, yielding $80,000 x 0.90 = $72,000 — a $20,000 swing that shows why loss control drives commercial auto pricing.

Exam tip: A mod of exactly 1.00 means the risk's losses matched expectations for its class — no debit, no credit.

Test Your Knowledge

An executive owns no personal car but frequently drives the company fleet and rented vehicles. Which endorsement gives her PAP-like coverage when using autos the business does NOT own?

A
B
C
D
Test Your Knowledge

A fleet's manual premium is $100,000 and its experience modification factor is 0.85. What is the modified premium, and what does the factor indicate?

A
B
C
D

Hired and Non-Owned Auto - The Exam's Favorite Gap

The most-tested commercial auto endorsement closes the gap for vehicles a business uses but does not own. A company that rents vehicles or whose employees drive their own cars on company business has no covered auto unless the policy is endorsed or written with the right symbols.

Endorsement / symbolCloses this gap
Hired Auto (Symbol 8)Liability for autos the business leases, hires, or borrows
Non-Owned Auto (Symbol 9)Liability arising from employees' personal autos used for business
Drive Other Car (DOC)Liability/medical/UM for an individual (often an executive) driving non-owned autos
Mobile EquipmentBridges the line between auto and CGL for certain equipment

Worked exam point: a sole proprietor insured only under a Business Auto policy has no personal auto coverage when driving a borrowed car for personal errands. The Drive Other Car endorsement supplies that individual coverage, functioning much like a Personal Auto Policy for a named person who owns no private vehicle of their own.

Mobile Equipment, Pollution, and the Trucking Endorsements

Several commercial auto endorsements address exposures that sit between auto and general liability.

EndorsementCloses this gap
Pollution Liability - Broadened Coverage for Covered AutosPollution from cargo/upset of a covered auto
Mobile EquipmentSpecified self-propelled equipment treated as autos
Trucking - Coverage for Certain OperationsOwner-operator and lessor exposures
Lessor - Additional Insured and Loss PayeeProtects a vehicle lessor

Exam Trap: The standard Business Auto pollution exclusion is broadened (not fully removed) by the pollution endorsement - it covers pollutants that are part of the upset/overturn of a covered auto or that escape from equipment used to propel the auto, but a release from transported cargo generally still needs separate environmental coverage.