Written by NotALawyer Legal AI · Reviewed by External Legal AI · Published July 2, 2026
Millions of U.S. drivers carry no insurance at all. If one of them hits you, uninsured/underinsured motorist (UM/UIM) coverage on your own policy is often the only real source of compensation. Some states require it; others only require insurers to offer it. The table on this page shows where your state lands.
UM coverage steps in when the other driver has no insurance — and, in many states, after a hit-and-run. UIM coverage applies when the at-fault driver's limits are too low for your damages. Either can pay medical bills, lost wages, and pain and suffering up to your policy limit.
Some states make UM coverage mandatory. Most others require insurers to offer it, and dropping it usually takes a written rejection — if no one ever signed one, the coverage may exist anyway. The state panel and 50-state table on this page show the rule where you live.
A UM/UIM claim is a first-party claim: you're asking your own insurance company to pay what the uninsured driver owed. Adjusters tend to defend these claims as hard as any other, and the policy's notice and cooperation duties still apply to you.
In some states, insuring multiple vehicles — or holding multiple policies in one household — lets you "stack" the limits together, sharply increasing the money available. Other states ban stacking or let the policy language decide. It's worth checking before accepting a limits-based denial.
The injury claim against the at-fault driver runs on your state's personal-injury deadline. The UM/UIM claim is a contract claim, and the policy may set shorter notice and suit deadlines of its own. Tracking both keeps either one from quietly expiring.
More on this topic: the Injuries & Accidents hub
This shows whether your auto insurer must include or merely offer uninsured/underinsured motorist coverage, how you can turn it down, and whether you can "stack" the limits of more than one policy. Each value is cited to the state statute or agency; a state with no sourced figure shows "Not yet sourced."
General information, not legal advice. Rules change and exceptions apply — confirm the current rule with the cited source for your state.
NotALawyer.com provides general legal information, not legal advice.