Stacked vs. Unstacked UM/UIM Coverage: Why Alaska Does Not Stack

By the FigureMyTax Editorial Team · How we calculate

In a state that stacks, every insured vehicle adds its uninsured and underinsured motorist limit to the total. In Alaska, a policy that insures several vehicles pays no more than the highest limit of any one coverage.

What stacking means

Most auto policies list a UM/UIM limit for each insured vehicle. Stacking adds those limits together after one injury, so a $100,000 limit on three vehicles becomes $300,000. Unstacked coverage pays only one limit. The idea matters only when your damages are larger than what the at-fault driver's insurer paid and larger than a single limit.

Alaska lets a policy pay only the highest limit

AS 28.22.221 says that if you are entitled to UM/UIM coverage under more than one coverage when two or more vehicles are insured under one policy, the maximum amount payable may not exceed the highest limit of any one coverage under that policy. Adding a vehicle to the policy does not add a limit.

A worked Alaska example

Say you carry a $100,000 limit on three vehicles, your damages are $250,000, and the at-fault driver's insurer paid its $50,000 limit. The unpaid damages are $200,000. A stacking state could pay up to $300,000, so the whole $200,000. Alaska pays up to the highest single limit, so $100,000. If you also have a UM/UIM policy from a different insurer with a $50,000 limit, the statute pays the policies in a priority order and that policy can add up to $50,000, for $150,000 in all. Try your own numbers in the Alaska UM/UIM stacking calculator.

Two policies from different insurers are different

The one-policy cap is not a cap on every policy you are covered by. When more than one policy applies, payments are made in a statutory order of priority, subject to the limit of each policy, starting with coverage on the vehicle you were occupying. The same statute says that for several policies from the same insurer in the same household, the maximum payable may be limited to the highest single limit. See what the statutes and courts say about anti-stacking language.

Stacking is not the same as portability

A related question is whether your UM/UIM coverage follows you into a vehicle insured under another policy. The Alaska Supreme Court answered yes in Umialik Insurance Co. v. Miftari (2024). That decision is about which policies can pay, not about multiplying limits; see how the combined coverage works.

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