What Illinois Requires Per Vehicle
Illinois law requires every registered vehicle to carry minimum liability coverage of $25,000 bodily injury per person, $50,000 bodily injury per accident, and $20,000 property damage. These limits apply to each car individually. If you insure two vehicles on one policy, both must meet 25/50/20. If you split them across separate policies, each policy must meet the minimums for the cars it covers.
The state also mandates uninsured motorist coverage at the same 25/50/20 limits unless you reject it in writing. Personal injury protection is not required. When you add a second or third vehicle to an existing policy, the carrier applies the same liability limits to the new car unless you specify otherwise. Confirming that every vehicle meets the statutory floor is the first step in structuring compliant coverage across a multi-car household.
Compare car insurance rates in your state
Get quotes from licensed carriers — no obligation, no spam, results in minutes.
Get Your Free QuoteIllinois Uninsured Motorist Rate
15.2%
More than one in seven drivers on Illinois roads carries no insurance, which is why the state mandates uninsured motorist coverage at the same 25/50/20 limits unless you reject it in writing. That rejection must be documented by your carrier.
Insurance Research Council, 2023
How Minimums Apply Across Multiple Vehicles
The 25/50/20 requirement is per vehicle, not per policy. A household with three cars on one policy must carry at least $25,000 per person, $50,000 per accident, and $20,000 property damage on each of the three vehicles. The policy's total limit does not aggregate across cars. If one vehicle is listed at 25/50/20 and another at 50/100/50, the first car meets the minimum and the second exceeds it, but the policy does not average the two.
This structure matters when you add a vehicle mid-term. The carrier rates the new car at the policy's existing liability limits unless you request a change. If your current vehicles carry 50/100/50 and you add a third car, the third car will typically be quoted at 50/100/50 as well. If you want the new car at 25/50/20 to lower the premium, you must specify that at the time of addition. The reverse is also true: adding a car at minimums does not pull down the limits on your existing vehicles.
A multi-car policy with one vehicle below 25/50/20 leaves that car uninsured under Illinois law, even if the other vehicles on the policy carry higher limits.
When Uninsured Motorist Coverage Is Mandatory
Uninsured motorist coverage pays your medical bills and lost wages when you are hit by a driver who carries no insurance or whose liability limits are too low to cover your damages. Because 15.2% of Illinois drivers are uninsured, the state mandates UM coverage at the same 25/50/20 minimums unless you explicitly reject it. The rejection must be in writing, signed by you, and kept on file by your carrier. If you reject UM coverage on a policy that insures multiple vehicles, the rejection applies to every car on that policy.
If you later decide you want UM coverage back, you can add it at renewal or mid-term by contacting your carrier. The coverage applies to all vehicles on the policy once added. When you add a new vehicle to an existing policy that already carries UM coverage, the new car is automatically covered at the same limits. If you rejected UM coverage on the existing policy, the new car will not have UM coverage unless you request it at the time of addition.
Related Articles
Structuring Liability Limits Across a Multi-Car Policy
Most carriers allow you to set different liability limits on different vehicles within the same policy, but the practice is uncommon. The more typical structure is uniform limits across all cars: if you carry 50/100/50 on one vehicle, the carrier applies 50/100/50 to every vehicle on the policy. This simplifies rating and reduces the chance of a coverage gap, but it also means you cannot selectively insure one car at minimums while carrying higher limits on another without splitting them across separate policies.
Splitting vehicles across two policies gives you the flexibility to insure one car at 25/50/20 and another at 100/300/100, but you lose the multi-car discount. The discount typically requires every vehicle to sit on the same policy. If the premium difference between 25/50/20 and 50/100/50 on one vehicle is smaller than the multi-car discount you would lose by splitting the policy, keeping all cars on one policy at the higher limit costs less overall.
When you own several vehicles but drive only one or two regularly, the rarely-driven cars still must meet the 25/50/20 minimum if they are registered. Dropping liability coverage below the statutory floor triggers a registration suspension. If a car is not driven, you can cancel the registration and drop liability coverage entirely, but the vehicle cannot be parked on public streets or driven on public roads while unregistered.
Illinois Average Annual Auto Premium
$863.96
Households insuring multiple vehicles at minimum liability limits typically pay less per car than this statewide average.
NAIC Auto Insurance Database Report, 2023
Proof of Insurance and Registration
Illinois requires proof of insurance at registration and during any traffic stop. The proof must show that the vehicle meets the 25/50/20 minimum. If you insure multiple vehicles on one policy, your insurance card lists every vehicle covered by that policy. If you split vehicles across separate policies, each car has its own proof-of-insurance card tied to the policy that covers it. Carrying the wrong card during a stop can result in a citation even if the vehicle is insured, because the officer cannot verify coverage from a card that does not list that vehicle.
When you add a vehicle to an existing policy, the carrier issues a new proof-of-insurance card that includes the newly-added car. Keep the updated card in every vehicle. If you buy a car mid-term, most carriers provide a grace period during which the new vehicle is covered under your existing policy without prior notification, but that grace period is typically 14 to 30 days. After the grace period expires, an unreported vehicle is not covered, and you are driving uninsured even if your other cars remain insured under the same policy.
Compare Carriers That Write Multi-Vehicle Policies in Illinois
Carriers vary in how they rate multi-vehicle policies and how much the multi-car discount offsets the cost of adding a second or third vehicle. Some carriers offer a larger discount when you add the second car than when you add the third. Others apply a flat percentage discount to every vehicle after the first. The only way to know which carrier's structure fits your household is to compare quotes that reflect your actual vehicle count and the liability limits you want on each car.
Illinois has 32 carriers writing auto insurance in the state, and most write multi-vehicle policies. Use the site's comparison tool to see which carriers offer the multi-car discount and how the discount applies to your specific household. Enter every vehicle you plan to insure, confirm that each meets the 25/50/20 minimum, and compare the total premium across carriers. The carrier with the lowest rate for one car is not always the lowest for three.