Stacked vs. Single-Limit UM/UIM Coverage in Iowa

By the FigureMyTax Editorial Team · How we calculate

Stacking adds the uninsured and underinsured motorist limits of several policies or vehicles together. Iowa enforces anti-stacking provisions, and the legislature states that an insured with more than one policy may recover up to the highest single limit.

What stacking means

A household may have more than one policy or vehicle with UM/UIM. Stacking adds those limits after one injury, so $100,000 and $50,000 become $150,000. Single-limit coverage pays only the highest applicable limit.

What Iowa law says

Iowa Code 516A.2(1)(b) declares abrogated a 1990 decision that had allowed interpolicy stacking against specific policy language, and says that enforcing the anti-stacking provisions in a motor vehicle policy does not frustrate the protection of the UM statute. Subsection (3) states the intent that an injured insured with more than one policy may recover up to the highest single limit under any one of them, paid by the insurers according to the policies' priority provisions.

Stacking forms exist

Subsection (2) directs the insurance commissioner to adopt rules so that policies, riders or endorsements providing for the stacking of UM and UIM with similar coverage are available in Iowa. So stacking is something you can buy, not something the statute gives you automatically.

A worked example

Suppose you are an insured under two policies with $100,000 and $50,000 of UIM, the at-fault insurer paid $25,000 and your damages are $250,000. With the usual single-limit form, the most is $100,000 (before any offset). With a stacking endorsement the cap could reach $150,000. Try your own numbers in the Iowa UM/UIM stacking calculator.

What to check

Look at your declarations pages and ask whether any policy carries a stacking endorsement. We did not read Iowa court decisions on how much UIM pays after the other driver's payment, so ask an attorney. See what section 516A.2 says and how UM and UIM work in Iowa.

This is general information, not legal advice, and the state comparisons above are illustrative, not an exhaustive survey. Confirm how Iowa's rules apply to your specific case with a licensed Iowa attorney.