Insurance companies and their policy terms differ as do state laws. So it varies within the insurance industry if a towed vehicle, such as a vehicle on a car trailer is covered or not by a motor vehicle policy or in your case whose insurance would cover the vehicle under various circumstances.

If your car is being pulling on a trailer behind another vehicle, the Liability coverage of the tow vehicle normally would extend for any damage caused by the trailer up to the limits and terms of the policy. The general rule is that a trailer being pulled by a covered auto, it is covered as long as the covered auto has appropriate coverage.

Liability coverage would cover if the trailer and towed car say broke loose and caused damage to other people's vehicles or property or caused bodily injury to others but not cover the trailer or vehicle on the car trailer.

So the car owner's auto insurance policy may provide Liability coverage when their trailer, or vehicle is attached, or being towed. Full coverages of Other Than Collision (Comprehensive) and Collision would normally have to be added to provide coverage for any damage to the trailer, especially while the trailer is unattached. With this coverage it would typically cover the trailer but not necessarily your vehicle on the trailer so the owner of the tow vehicle would have to check with their insurer about what coverages they have and if any would extend to the trailer and/or vehicle being towed.

Damages to your vehicle while it is towed would usually be claimed against the physical damage coverages (Collision and Comprehensive) of your own auto insurance policy. So if a rock or other road debris struck your vehicle and caused damage during the cross country tow typically you would have to make a claim under your vehicle's physical damage coverages and not the insurance of the owner of the tow vehicle.

Since insurance policy terms and carrier's guidelines differ regarding trailers and towed vehicles so it is best to read through the terms of your specific auto insurance policy and speak to your agent to see how your vehicle would be covered under your current policy if it was towed on a trailer behind someone else's vehicle. The person that has the trailer and would be towing your vehicle should also check to see what their current car insurance policy would cover in this situation. If they have "full coverage." they should ask if it would cover the trailer and your car being towed.

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