Uninsured motorist coverage (UM) pays for your injuries, and your passengers’ injuries, when a driver with no insurance or a hit-and-run driver causes a crash. Underinsured motorist coverage (UIM) pays when the at-fault driver has insurance but not enough to cover your losses. In some states, UM also pays to repair your car.
About 1 in 7 drivers had no insurance in 2023, according to the Insurance Research Council, and 1 in 3 were either uninsured or underinsured. UM is required in 21 jurisdictions, and most other states make insurers offer it.
Key Takeaways
- UM covers injuries caused by an uninsured or hit-and-run driver. UIM covers the gap when the at-fault driver’s liability limits are too low for your losses.
- UM is required in 21 jurisdictions, including New York, Illinois and Virginia. In most other states, insurers must offer it, and you can turn it down.
- UIM works differently by state. Some states subtract what the at-fault driver’s insurer paid, while others pay on top of it, which can change your total recovery a lot.
- Hit-and-run claims can come with conditions, such as physical contact, a prompt police report or, for car damage, an identified driver or license plate.
What Uninsured Motorist Coverage Pays For
The NAIC’s consumer shopping tool says UM bodily injury coverage “pays for your bodily injuries and those of your passengers if you are hit by a hit-and-run driver or an uninsured driver who is at fault.” That typically includes medical bills and other losses you could have claimed from the other driver if they’d been insured.
UM usually protects more than the driver. Wisconsin’s insurance regulator, for example, says UM applies to injuries “you, your family, and other occupants of your vehicle incur” when hit by an uninsured or hit-and-run driver. The details depend on your state and policy.
Uninsured Motorist Property Damage
Some states add property damage to UM, which pays to fix your car when an uninsured driver is at fault. The District of Columbia, Maryland, New Jersey, South Carolina, Vermont, Virginia and West Virginia include property damage in their required UM. Other states handle it differently. In California, uninsured motorist property damage pays the lesser of your car’s actual cash value or $3,500, and only if the uninsured car actually hit yours and the other driver or the vehicle’s license plate is identified. If you have collision coverage there, it pays only your collision deductible, up to $3,500.
What Underinsured Motorist Coverage Pays For
The NAIC’s auto insurance guide says, “Underinsured motorist coverage pays when an at-fault driver doesn’t have enough insurance to fully pay for your loss.” Say another driver carries a $30,000 bodily injury limit, but your medical bills and lost income from the crash come to $150,000. UIM is what can cover some of the difference.
How UIM Is Calculated Depends on Your State
States use two main approaches, and the difference can be large.
- Offset approach. UIM applies only when the at-fault driver’s limits are lower than your UIM limits, and your insurer subtracts what that driver’s insurer paid. Illinois, California and Wisconsin work this way, along with Maryland’s standard coverage. Your total recovery tops out at your own UIM limit.
- Add-on approach. UIM pays on top of what the at-fault driver’s insurance paid, up to your UIM limit. Virginia’s statute says UIM is paid “without any credit” for the other driver’s coverage unless a named insured signs an election to reduce it. Maryland’s enhanced UIM works this way too.
Here’s a hypothetical example. The at-fault driver has $30,000 of bodily injury liability per person, your injuries total $150,000, and you carry $100,000 of UIM:
| Offset approach | Add-on approach | |
|---|---|---|
| Paid by the at-fault driver’s insurer | $30,000 | $30,000 |
| Paid by your UIM | Up to $70,000 | Up to $100,000 |
| Your total recovery | Up to $100,000 | Up to $130,000 |
Maryland shows both side by side. On its enhanced UIM page, the Maryland Insurance Administration says enhanced UIM is currently the default for new policies issued since July 1, 2024, and you have to opt out in writing if you don’t want it. It also notes that enhanced coverage raises your premium.
Which States Require Uninsured Motorist Coverage?
| Requirement | States |
|---|---|
| UM required (21 jurisdictions) | Connecticut, District of Columbia, Illinois, Kansas, Maine, Maryland, Massachusetts, Minnesota, Missouri, Nebraska, New Jersey, New York, North Carolina, North Dakota, Oregon, South Carolina, South Dakota, Vermont, Virginia, West Virginia and Wisconsin |
| UIM also required (11) | Connecticut, Kansas, Maine, Minnesota, Nebraska, North Carolina, North Dakota, Oregon, South Dakota, Vermont and Virginia |
| Included unless you reject it in writing (examples) | Arkansas (UM), Florida (UM, on policies that include bodily injury liability), Georgia (UM), Indiana (UM and UIM), Tennessee (UM), Texas (UM and UIM) and Washington (UIM, which also covers uninsured drivers) |
| Special case | New Hampshire doesn’t require insurance, but a policy that’s sold must include UM equal to your liability limits |
In most other states, insurers have to offer the coverage, and you can turn it down. The Texas Department of Insurance explains: “Insurance companies must offer you this coverage. If you don’t want it, you must tell the company in writing.” Rejection rules vary by state, so read any form carefully before you sign it. RateFrog’s guide to what minimum coverage covers explains how these requirements fit with the rest of a basic policy.
How Many Drivers Are Uninsured?
The Insurance Research Council estimated that 15.4% of drivers, or more than 1 in 7, were uninsured in 2023. It also found that 33.4% were either uninsured or underinsured. IRC’s estimate is based on insurance claims, not a count of registered cars. Rates vary widely by state:
| Highest uninsured rates, 2023 | Lowest uninsured rates, 2023 |
|---|---|
| Mississippi: 28.2% | Maine: 5.7% |
| New Mexico: 24.1% | Utah: 6.2% |
| District of Columbia: 23.1% | Idaho: 6.4% |
| Michigan: 22.3% | Wyoming: 6.7% |
| Tennessee: 21.3% | Montana: 7.2% |
State figures come from the Insurance Information Institute, which summarizes IRC’s study.
Does Uninsured Motorist Coverage Cover Hit-and-Run Accidents?
Often, yes. The NAIC and the Texas Department of Insurance both say UM pays if you’re injured by a hit-and-run driver. But states and policies can add conditions:
- Physical contact. California’s law requires the injury to come from physical contact with the hit-and-run vehicle, a police report within 24 hours and a sworn statement to your insurer within 30 days.
- A prompt police report. Maryland’s regulator says “most insurance companies require you report the loss to the police department as soon as possible,” and some policies set a specific deadline.
- An identified driver or vehicle for car damage. California’s uninsured motorist property damage coverage doesn’t pay unless the driver or license plate is identified.
If you’re hit and the other driver leaves, call the police right away and tell your insurer as soon as you can.
What Is Stacking?
Stacking lets you combine UM or UIM limits across several vehicles. Pennsylvania’s insurance department explains that with stacking, “your limit of coverage for each covered vehicle on your policy is multiplied by the number of vehicles on the policy.” In Pennsylvania, stacked coverage applies unless you reject it, and rejecting it lowers your premium. Many states limit or don’t allow stacking, so ask your insurer what applies where you live.
How to Decide How Much UM and UIM to Carry
Questions like these can help you decide:
- If an uninsured driver seriously injured you, how would you pay medical bills your health insurance doesn’t cover?
- Could you replace your income if you missed months of work?
- Do you often have passengers who could be hurt in your car?
- How common are uninsured drivers in your state?
- Does your state use the offset or add-on approach to UIM?
If you have collision coverage, it can already pay to repair your car after a crash with an uninsured driver, minus your deductible. UM property damage, where it’s available, may still help. In California, for example, it pays your collision deductible. RateFrog’s guide to minimum vs. full coverage walks through how these pieces work together. When you’re ready to shop, you can compare car insurance quotes with the same UM and UIM limits so the prices are comparable.
Frequently Asked Questions
Is Uninsured Motorist Coverage Required?
It’s required in 21 jurisdictions. In states such as Arkansas, Georgia, Indiana and Texas, it’s included unless you reject it in writing, and most other states require insurers to offer it.
Does Uninsured Motorist Coverage Have a Deductible?
It can. The Texas Department of Insurance, for example, says you must pay a deductible for uninsured and underinsured motorist claims. Check your declarations page for your own policy.
Does UM Cover Me If the Other Driver Is Only Partly at Fault?
It depends on your state. In Maryland, for example, the state’s insurance regulator says uninsured motorist coverage only applies if the other driver is found to be 100% at fault.
Is Underinsured Motorist Coverage the Same as Uninsured Motorist Coverage?
No. UM applies when the at-fault driver has no insurance or can’t be found. UIM applies when the at-fault driver has insurance but not enough. Many policies sell them together.
Sources
- NAIC: Consumer Shopping Tool for Auto Insurance (PDF)
- NAIC: A Consumer’s Guide to Auto Insurance (PDF)
- Texas Department of Insurance: Auto Insurance Guide
- Wisconsin Office of the Commissioner of Insurance: Auto Insurance
- Maryland Insurance Administration: Uninsured Motorist Claims
- Maryland Insurance Administration: Enhanced Underinsured Motorist Coverage
- Virginia Code section 38.2-2206
- Illinois 215 ILCS 5/143a-2
- California Insurance Code section 11580.2
- California Insurance Code section 11580.26
- Pennsylvania Insurance Department: Auto Insurance Guide (PDF)
- Insurance Research Council: Uninsured and Underinsured Motorists
- Insurance Information Institute: Uninsured Motorists