Illinois Requires Uninsured Motorist Coverage on Every Policy
You're adding a second vehicle to your Illinois auto policy and the carrier quote includes uninsured motorist coverage you didn't request. That's not an upsell—it's a state mandate. Illinois is one of roughly a dozen states that require uninsured motorist (UM) coverage on every auto insurance policy, and you cannot waive it unless you do so in writing.
The requirement applies whether you insure one car or five. When you add vehicles to an existing policy, the UM coverage extends to all of them under the same per-person and per-accident limits. Understanding how those limits work across multiple vehicles—and what happens when an uninsured driver hits one of your cars—clarifies why the mandate exists and what protection it actually provides.
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Get Your Free QuoteIllinois Uninsured Motorist Rate
15.2%
More than one in seven drivers on Illinois roads carries no liability insurance. That rate is higher than the national average and creates real exposure for insured households, especially those with multiple vehicles on the road daily.
Insurance Research Council, 2023
The Mandate Applies Per Policy, Not Per Vehicle
Illinois law requires every auto insurance policy to include uninsured motorist bodily injury coverage with minimum limits of $25,000 per person and $50,000 per accident. Those limits mirror the state's minimum liability requirements, and they apply to the policy as a whole—not to each vehicle individually.
When you add a second or third car, the UM coverage doesn't stack. A household with three vehicles on one policy still has $25,000 per person and $50,000 per accident in UM protection. If an uninsured driver causes an accident involving two of your household's cars and injures three people, the $50,000 per-accident cap applies to all claims combined, regardless of how many of your vehicles were involved.
This structure differs from liability coverage, which applies separately to whichever vehicle you're driving at the time of an accident. UM coverage protects you and your household members as injured parties, so the limits function as a shared envelope across all covered vehicles and all covered people.
Adding vehicles to your policy does not increase your uninsured motorist limits—the per-person and per-accident caps stay fixed unless you request higher coverage.
How Uninsured Motorist Coverage Works Across Multiple Vehicles
Imagine your household owns three vehicles: a sedan your spouse drives to work, an SUV you use for errands, and a truck your teenager drives to school. All three sit on one Illinois policy with the state-minimum $25,000/$50,000 UM coverage. An uninsured driver runs a red light and causes a crash involving both the sedan and the SUV. The at-fault driver has no insurance and no assets.
But if a third household member in one of the vehicles also sustained injuries pushing total medical costs past $50,000, the per-accident limit would cap the payout, leaving the excess uncompensated unless you carried higher UM limits.
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You Can Reject UM Coverage Only in Writing
Illinois allows you to reject uninsured motorist coverage, but the rejection must be explicit and in writing. Carriers typically present a rejection form at the time you purchase or renew a policy. If you don't sign the form, the coverage stays on the policy by default.
Most households with multiple vehicles do not reject UM coverage. The 15.2% uninsured motorist rate in Illinois means the risk of an at-fault driver with no insurance is material, and rejecting UM leaves you dependent on your own health insurance and the at-fault driver's ability to pay out of pocket—which is often zero. For multi-car households, the exposure multiplies: more vehicles on the road daily means more opportunities for an uninsured driver to cause a crash involving one of your cars.
If you do reject UM coverage and later want to add it back, you can request it at any policy change or renewal. The carrier will add it with an effective date tied to the policy change, and the premium adjusts accordingly.
Illinois Minimum UM Limits
$25,000 / $50,000
The state-mandated uninsured motorist minimums match the liability minimums: $25,000 per person for bodily injury, $50,000 per accident. These limits apply to the policy, not to each vehicle, so adding cars does not increase your UM protection unless you request higher coverage.
Illinois Department of Insurance
Higher UM Limits Are Available and Often Recommended
The cost to increase UM limits is typically modest relative to the additional protection, especially for households with multiple vehicles and multiple drivers.
A household with three cars and four drivers faces higher aggregate exposure than a single-driver household. If two household members are injured in the same accident caused by an uninsured driver, the per-accident cap becomes the binding constraint.
Compare Carriers That Write Multi-Vehicle Policies in Illinois
Not every carrier offers the same UM limit options or charges the same premium for higher coverage. When you're structuring a multi-car policy, request quotes with UM limits above the state minimum and compare the incremental cost across carriers.
Start by confirming your current UM limits if you already have an Illinois policy. Then request quotes with higher limits from carriers that write multi-vehicle policies in the state. The comparison clarifies what additional protection costs and whether your current coverage leaves gaps when multiple household vehicles and drivers are on the road.