Coverage and State Rules

Uninsured and Underinsured Motorist Coverage Explained

Uninsured and Underinsured Motorist Coverage Explained
Photo: @marcusbellamy / Unsplash

Not every driver carries enough insurance, or any at all. This coverage protects you when the person who hits you can’t pay.

Quick checklist

  • Uninsured motorist (UM) coverage pays for your injuries if a driver without insurance causes an accident.
  • Underinsured motorist (UIM) coverage helps when the at-fault driver’s limits are too low to cover your costs.
  • Many policies treat hit-and-run drivers as uninsured, subject to conditions such as prompt police reports.
  • Some states require UM or UIM coverage; others let you reject it in writing.
  • Matching your UM/UIM limits to your own liability limits is a common rule of thumb.

Even though nearly every state requires car insurance, many drivers are uninsured, and many others carry only the state minimum. If one of them injures you, their insurance may not cover your costs.

Uninsured motorist coverage (UM)

UM pays for your medical bills, lost wages and pain and suffering, up to your policy limits, when a driver without insurance is at fault. Many policies also apply UM to hit-and-run accidents.

Underinsured motorist coverage (UIM)

UIM steps in when the at-fault driver has insurance, but not enough. For example, if your injuries cost $80,000 and the other driver’s policy pays only $25,000, UIM can cover the difference, up to your limit.

Hit-and-run claims

If you’re hit by a driver who flees:

  • Call the police right away and get a report.
  • Notify your insurer promptly.
  • Collect any evidence, such as photos, witness details or camera footage.

Policies often require prompt reporting for hit-and-run claims.

Driver tip

Check your declarations page. If your UM/UIM limits are much lower than your liability limits, ask your insurer what it would cost to raise them.

State rules

Some states require UM or UIM coverage. Others require insurers to offer it but let you reject it in writing. Rules on property damage coverage also vary, so check your state insurance department’s guidance.

Choosing limits

A common approach is to match your UM/UIM limits to your own liability limits. Consider your health insurance, disability coverage and how much income you’d lose after a serious injury.

If you live in a no-fault state, see how PIP coverage works alongside UM. And if you’re ever in an accident, start with our checklist.

Driver questions

Does UM cover damage to my car?

Uninsured motorist property damage (UMPD) is available in some states. Elsewhere, collision coverage pays for damage to your car, minus your deductible.

Does UM coverage protect my passengers?

Generally, yes. It usually covers you, household members and passengers in your car.

Does it cover me as a pedestrian?

In many cases, yes. UM and UIM often protect you if you’re hit by an uninsured driver while walking or cycling.

Is it expensive?

It’s usually one of the less expensive parts of a policy compared with the protection it provides. Ask your insurer for a quote at different limits.

Car insurance rules vary by state and by policy. This guide is general information, not legal or insurance advice; check your policy and your state insurance department for details.