If another driver causes a crash, you might assume their insurance will pay your medical bills and other losses. But some drivers have no insurance. Others may flee the scene, leaving you with no clear way to collect. That’s where uninsured motorist coverage (often called UM coverage) can matter.
UM coverage is designed to protect you when the at-fault driver can’t pay because they’re uninsured (or sometimes unidentified in a hit-and-run). It can help cover injuries and related losses up to your policy limits. In this guide, you’ll learn what UM coverage is, what it commonly covers, how hit-and-run claims work, and the policy details that can change the outcome of a real claim.
Quick tip: If you have your policy documents handy, check your declarations page (often called the “dec page”). That’s where UM coverage and limits are usually listed.
What is uninsured motorist coverage?
Uninsured motorist coverage is part of an auto insurance policy that may pay for certain losses when you’re harmed by a driver who has no liability insurance. It’s different from the liability coverage you carry to protect other people when you cause an accident. UM is usually about protecting you and your passengers when someone else is responsible but can’t cover the costs.
Example: You’re stopped at a red light and a driver rear-ends you. You later learn the driver has no insurance. UM coverage may step in (depending on your state and policy terms) to help with covered losses up to your UM limits.
If you want the big picture of how coverages fit together, see: What Does Car Insurance Cover?
UM vs. UIM: what’s the difference?
These two terms are easy to confuse:
- UM (Uninsured Motorist): the at-fault driver has no insurance (or cannot be identified in some hit-and-run cases).
- UIM (Underinsured Motorist): the at-fault driver has insurance, but their limits are too low to cover the full loss.
Many insurers offer UM and UIM together, but the rules and labels can vary by state. The most accurate answer is always the wording on your declarations page and policy.
What does uninsured motorist coverage typically pay for?
UM coverage is often split into different parts. Not every state offers every version, and some policies package them differently. Here are the common categories.
UM bodily injury (UMBI)
UM bodily injury (UMBI) is the most common form of uninsured motorist coverage. It may help pay for injuries to you and your passengers caused by an uninsured driver. Depending on state rules and policy language, it may include:
- Medical bills related to crash injuries
- Lost wages if you can’t work
- Pain and suffering (where allowed)
- Other injury-related damages that state law and your policy recognize
UMBI limits are often shown as two numbers (for example, “per person / per accident”). Your declarations page will show how your limits are structured.
UM property damage (UMPD)
UM property damage (UMPD) may help repair or replace your vehicle (or other property) when an uninsured driver damages it. UMPD is not available everywhere, and in some places it’s limited or works differently depending on what other coverages you have.
It’s also common for drivers to rely on collision coverage for vehicle repairs, even when the other driver is uninsured. Collision is separate from UM and may apply regardless of who is at fault (subject to your deductible).
What UM coverage usually does not cover
UM can be extremely valuable in the right situation, but it’s not “everything coverage.” Common limitations include:
- Policy limits: UM pays up to the limits you purchased—serious losses can exceed those limits.
- Not a replacement for comprehensive: If your car is damaged by theft, vandalism, hail, or a fallen tree, that’s typically a comprehensive scenario, not UM.
- Rules can be strict for hit-and-run: You may need timely reporting and proof that another vehicle caused the incident.
- Exclusions and definitions: The policy defines who is an insured person and what counts as an uninsured/unknown driver.
UM is best understood as protection against a specific financial risk: being harmed by a driver who cannot pay.
Does UM coverage apply in a hit-and-run?
In many states, a hit-and-run can trigger uninsured motorist coverage if the at-fault driver cannot be identified. But this is one of the areas where policy requirements matter the most.
Common requirements can include:
- Reporting the crash to police within a certain timeframe
- Providing evidence that another vehicle caused the crash (photos, debris, witnesses)
- Cooperating with your insurer’s investigation
If you’re ever in a hit-and-run, try to document what you can safely: vehicle description, plate number if possible, photos of the scene, and witness contact info. Documentation often makes the difference between a smooth claim and a disputed one.
Who is covered by uninsured motorist coverage?
This varies, but UM commonly covers:
- You (the named insured)
- Family members in your household (in many policies)
- Passengers riding in your insured vehicle
In some cases, UM may also apply if you’re struck as a pedestrian or cyclist, but not all policies treat that the same way. The safest approach is to check the “Who is an insured” and UM sections of your policy.
Policy limits, stacking, and offsets
UM coverage has limits, and those limits matter most in serious injury claims. There are also two concepts that can change how much is available:
- Stacking: In some states, you may be able to combine (stack) UM limits across multiple insured vehicles. Other states limit or prohibit stacking.
- Offsets: Some policies or state rules reduce UM payments by amounts paid from other sources (exact rules vary widely).
Because these rules are state-specific, your declarations page and policy language are the best place to confirm what applies to you.
Related: Car Insurance Policy Limits: What They Mean and How They Work
How to file a UM claim
If you think UM coverage may apply, this checklist helps you stay organized:
- Get medical care and follow up—health comes first.
- Document the scene: photos, vehicle positions, damage, road conditions, and any relevant signs or signals.
- Collect witness info if anyone saw the crash.
- Report the crash when appropriate (especially for hit-and-run scenarios).
- Notify your insurer promptly and ask how they handle UM claims in your state.
- Keep records: medical bills, time missed from work, repair estimates, and claim communications.
If you want a broader view of the overall process, see: Car Insurance Claims Process: Steps That Real Claims Follow
How much UM coverage should you carry?
There isn’t a universal “perfect number,” but there are practical ways to think about it:
- Match your liability limits if possible: Many drivers choose UM limits similar to their bodily injury liability limits.
- Consider injury costs: Even a “moderate” injury can lead to significant bills, time off work, and long-term rehab.
- Look at what gaps you want to avoid: If an uninsured driver hits you, UM may be the main coverage protecting your household financially.
If you’re comparing coverages, you may also want to review what you have for medical-related coverages (like PIP or MedPay, depending on your state) and how they interact with UM claims.
FAQ
Is uninsured motorist coverage required?
It depends on your state. Some states require it, others require insurers to offer it, and some make it optional. Your declarations page will show whether you have it and what limits you chose.
Is UM coverage the same as “full coverage”?
No. “Full coverage” isn’t a standardized insurance term. UM is one specific coverage. Many people use “full coverage” informally to mean liability + comprehensive + collision, but that phrase can be misleading.
Will UM pay for my car repairs?
Sometimes—if you have UM property damage (UMPD) and it’s available in your state. Many drivers still rely on collision coverage for repairs after a crash with an uninsured driver.
Important to know
Car Policy Answers is an independent educational website. We do not sell insurance, provide quotes, or recommend insurance companies.
This article is for general educational purposes only. Auto insurance rules vary by state, and coverage depends on your policy terms and limits. For advice about your situation, consider speaking with your insurer or a qualified professional in your state.