Question: Will insurance companies cover rust damage?
Answer: No, auto insurance coverages do not typically cover rust damage to a vehicle. Rust is usually just considered normal wear and tear of the vehicle. Physical Damage coverages of Collision and Comprehensive cover damages to the vehicle from an incident, not something like rust that usually appears over time.
If, however, the rust is due to an incident and the repair was not made correctly or you had water damage to the vehicle due to floods, hurricane winds and water, then you could check to see if your Comprehensive cover would cover your resulting rust damage.
Comprehensive insurance normally covers your vehicle for losses resulting from incidents other than collision (OTC). For example, comprehensive insurance covers damage to your car if it is stolen; or damaged by flood, fire, or animals. This optional auto insurance coverage pays to fix your vehicle less the deductible you choose and may over rust damage depending upon how and why it happened.
There are exclusions to OTC, mainly normal wear and tear and mechanical failures that are not due to a covered event or loss. If the rust is found not to be caused by an accident or other incident covered by your auto insurance policy but due to normal wear and tear, then the repairs needed would not be covered by your auto insurance policy.
You can read through the terms of your OTC auto insurance policy and speak with your agent to find out for certain if any of the repairs that need to be made to your vehicle due to the rust will be covered since state laws and insurance policies do differ.
Likely to cover the repairs that you need to make due to the rust on your vehicle; you would need to look at the car's warranty (if it is still covered and this damage falls into their coverages). Or if you have mechanical breakdown insurance (MBI) on it you could see if this type of damage would be covered with the MBI, though again normal wear and tear is not usually covered by this type of insurance either.