Is Uninsured/Underinsured Motorist Coverage Required by Law?
Whether uninsured and underinsured motorist coverage is required, optional, or something in between depends entirely on which state a driver lives in — there’s no single national answer.
The short answer
Requirements for uninsured and underinsured motorist coverage vary significantly by state. Some states require insurers to include it on every policy unless the driver actively waives it in writing. Others require insurers to offer it, but leave the decision to add it entirely up to the driver. And a smaller number of states don’t require it to be offered at all. Because the rules differ this much, the only way to know what applies to a specific policy is to check the state’s requirements and the policy documents directly.
The range of state approaches
At one end, some states build uninsured and underinsured motorist coverage into every standard policy by default, treating it similarly to liability coverage in terms of how automatic it is — a driver in one of these states would need to actively decline it to go without it. In the middle, many states require insurers to offer the coverage and disclose it, but don’t require drivers to purchase it, which puts the decision squarely on the policyholder at the time the policy is written. At the other end, a handful of states don’t mandate that insurers even offer it, meaning it may not appear as an option at all unless a driver specifically seeks out a policy that includes it.
Why “required” and “offered” aren’t the same thing
Even in states that require insurers to offer the coverage, that’s different from requiring drivers to buy it. Declining coverage that was offered, sometimes through a written waiver, is a common outcome, particularly when a driver is focused on minimizing the premium. That waiver is a real decision with real consequences, not a formality, since it determines whether there’s a backstop if the driver involved in a future accident turns out to have too little insurance or none at all.
Why it’s worth carrying even where it’s optional
A meaningful share of drivers on the road carry no insurance at all, or carry only the state’s minimum required liability limits, which can be too low to cover a serious accident’s full cost. Because the actual rate varies by state and changes over time, it’s worth checking current figures for a specific area rather than relying on a fixed number, but the underlying pattern — that a real portion of drivers are uninsured or underinsured — is common enough across the country that the coverage isn’t a niche concern. In states where it’s optional, that pattern is often the strongest argument for adding it rather than declining, since liability coverage carried by other drivers is something no individual policyholder can control.
What to check on a specific policy
Because the state sets the baseline rule but the policy itself determines the actual coverage, the practical step is to look at the declarations page, or ask directly, to see whether uninsured and underinsured motorist coverage is included, what the limits are, whether those limits can be stacked across vehicles, and whether it was ever waived. A driver who assumes the coverage exists simply because most policies have it can be surprised to find it was declined during an earlier renewal and never added back.
The bottom line
There’s no single national rule on whether uninsured and underinsured motorist coverage is required — it ranges from automatic, to offered-but-optional, to not required to be offered at all, depending on the state. Understanding where a given state falls, and checking what a current policy actually includes, is the only reliable way to know what protection exists.