How do UM and UIM claims work in Arizona?

What the coverage actually is

Uninsured motorist coverage pays what a no-insurance driver should have paid; underinsured coverage pays the gap when their limits are too small for your injuries. Your insurer stands in the at-fault driver's shoes: you still have to prove fault and prove damages, and the company across the table now has every incentive the other driver's insurer would have had. The logo on the letterhead is yours; the adjuster's job is not.

The consent-to-settle trap

Here is the mistake that costs people their UIM coverage: accepting the at-fault driver's policy limits without first getting their own insurer's written consent. Most policies require it, because settling can wipe out the insurer's right to chase the at-fault driver. Take the check first and the UIM claim can vanish on a technicality. The sequence matters, get consent in writing, then settle, and it is one of the first things we control in any underinsured case.

Hit-and-run and phantom drivers

A driver who flees, or one who runs you off the road without contact, is an uninsured driver for coverage purposes. Report the crash to police immediately and to your insurer promptly; for no-contact crashes, policies often want corroboration beyond your own account, a witness, camera footage, physical evidence. The faster the report, the harder the claim is to doubt.

Stacking, households, and the deadline question

Whether coverage from multiple vehicles or multiple household policies can be combined depends on the policy language, and that language deserves a professional read before anyone concludes what the total available coverage is. Timing deserves the same respect: UM and UIM claims are contract claims, and their deadlines run differently than the two-year crash deadline, sometimes by policy terms. Treat the UM clock as its own deadline question from day one.

Your leverage: Arizona's good-faith duty

Because a UM or UIM claim is first-party, your insurer owes you a duty of good faith, and Arizona enforces that duty with real consequences. An insurer that lowballs without a basis, delays without a reason, or refuses to investigate is exposed beyond the policy itself. That leverage changes negotiations, and using it well is much of what a lawyer adds to these claims.

Related: Arizona Insurance Minimums · Arizona Insurance Bad Faith · Dealing With the Adjuster · All Common Questions

Injured in Texas? Texas applies different rules to many of the topics on this page. See Uninsured & Hit-and-Run (Texas) or all Texas answers.

This page is general information about Arizona law, not legal advice about your specific situation. Deadlines and outcomes depend on facts; talk to a lawyer about yours.