Uninsured Motorist Coverage (UM): How it Works, Requirements

What Is Uninsured Motorist Coverage (UM)?

Uninsured motorist (UM) coverage is a component of an auto insurance policy that provides coverage when the policyholder is in an accident with someone who does not have insurance. It is an add-on to a standard auto policy and pays for injuries to the policyholder and passengers, and in some instances for damage to property, if the other driver is legally responsible for the accident but uninsured. In some states, it is required that auto insurance policies include uninsured motorist coverage.

Key Takeaways

  • Uninsured motorist coverage (UM) is an add-on coverage for auto policies that will pay for injuries and damages caused by an uninsured driver.
  • Hit-and-run drivers are also considered uninsured motorists.
  • Uninsured motorist coverage usually adds only a small cost to an auto insurance policy but provides beneficial coverage.

Understanding Uninsured Motorist Coverage (UM)

An uninsured motorist (UM) is an at-fault driver who has no auto insurance, does not have insurance that meets state-required minimum liability amounts, or whose insurance company is unwilling or unable to pay the claim. A hit-and-run driver would also be considered an uninsured motorist. If you are in an accident with an uninsured motorist and do not have uninsured motorist coverage, you may not receive payments, even if the other person is at fault.

How Uninsured Motorist Coverage Works

State laws generally mandate that motorists carry some level of automobile liability insurance coverage, and these requirements vary from state to state. Nineteen states plus Washington D.C. require that policies include uninsured motorist (UM) coverage. New Hampshire and Virginia are the only U.S. states that do not require a minimum amount of auto insurance coverage.

Despite these mandates, one in every eight U. S. drivers on the road does not have insurance, reports the Insurance Research Council. The organization's latest report on this subject found that Florida had the highest number of uninsured drivers at 26.7%, followed by Mississippi, New Mexico, Michigan, and Tennessee. The state with the lowest number of uninsured motorists is Maine with 4.5%

Uninsured motorist coverage is designed to protect you against financial losses stemming from an accident in which the other driver lacks adequate coverage. If you are involved in an accident and the other driver is at fault, you'd file a claim with that driver's insurance company. If the claim is successful, you could use the proceeds to repair your car or pay for medical bills associated with injuries from the accident.

In cases where the driver lacks sufficient coverage or any type of car insurance at all, having uninsured motorist coverage can minimize anything you might have to pay toward vehicle repairs or medical bills. Again, this may be optional, depending on where you live but having this coverage could offer some reassurance if you're involved in an accident.

There are two types of uninsured motorist coverage. Uninsured motorist bodily injury covers medical bills related to a crash, while uninsured motorist property damage pays for damage to your car.

Uninsured Motorist vs. Underinsured Motorist Coverage

In addition to uninsured drivers, there are also those who have some insurance but it may not be enough to cover the full cost of a claim if there's an accident. Again, most states require drivers to have minimum levels of at least liability coverage. But a driver who's hoping to save on their car insurance might opt for the lowest coverage amounts, which could lead to financial consequences for other drivers if they're involved in an accident.

It's important to be aware of this distinction since uninsured motorist coverage is not the same as underinsured motorist coverage, which would cover a situation in which the at-fault driver did not have enough insurance to fully cover the other injured party's damages. However, these two types of coverage may be bundled together. Either separately or together, they are usually a relatively inexpensive add-on to an auto insurance policy but provide beneficial coverage.


Some states allow you to "stack" uninsured motorist and underinsured motorist coverage when you have multiple vehicles listed on the same policy.

Requirements for Claiming Uninsured Motorist Coverage

During the investigation of an accident, if the at-fault driver does not have insurance, the police will inform the other involved drivers. If the police do not respond to the accident or, in the case of a hit-and-run crash, try to gather as much information as possible. Ask for names, addresses, and phone numbers of potential witnesses. If possible, get the license plate number of the other car and take photographs of the accident scene. 

As soon as possible, file a claim with your insurance company, providing all the information you may have. Some insurance providers will have a limit on how long you can wait before you file your uninsured claim. These limits will vary by company.

As the insurance company settles your claim, it will want copies and billings from all medical care received and any automobile repair that resulted from the event. If the insurance provider decides the costs submitted with the claim are unnecessary or not related to the accident, they will deny those amounts. If the policyholder disagrees with the decision of the insurance provider, the case will usually go to binding arbitration.


Any time you're involved in a car accident, it's important to first check for injuries and move the vehicle off the roadway if necessary.

Article Sources
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  1. Insurance Information Institute. "Background on: Compulsory Auto/Uninsured Motorists." Accessed April 26, 2021.

  2. Insurance Research Council. "News Release: One in Eight Drivers Uninsured." Accessed Mar. 5, 2021.