Why every California driver should carry uninsured and underinsured motorist (UM/UIM) coverage

By Tyler Vance, California attorney · Updated 2026-09-28 · 7 min read

General information, not legal advice. Every situation is different. If you have a deadline or court papers, don't wait on a guide. Call (562) 644-4186.

If you take one thing from my injury guides, I'd like it to be this: check that your auto policy includes uninsured and underinsured motorist coverage, at limits you'd be comfortable relying on. After a crash, the at-fault driver's insurance is often the only money available, and sometimes there isn't enough of it, or there's none. UM/UIM coverage is insurance you buy for yourself to deal with that problem. This is general information, not advice about your policy or your case.

The problem: the other driver's coverage may be small or missing

California's minimum liability limits are set by Vehicle Code section 16056. For policies issued or renewed on or after January 1, 2025, they are $30,000 for injury or death of one person, $60,000 for injury or death of two or more people in one accident, and $15,000 for property damage. A driver who carries only the minimum may have far less coverage than a serious injury costs. Some drivers carry no insurance at all, and some drive away.

What UM/UIM coverage does

Under Insurance Code section 11580.2, uninsured motorist coverage pays you, within your policy limits, the amounts you would be legally entitled to recover as damages for bodily injury or wrongful death from the owner or operator of an uninsured motor vehicle. In plain English, you make a claim against your own policy for what the at-fault driver owes you. The statute treats an "underinsured" vehicle as a type of uninsured vehicle, and it also covers some situations where the at-fault driver's insurer denies coverage or becomes insolvent.

To be clear about the limits: your coverage is capped at the limits you buy. "Covered no matter what the other driver has" means you have your own source of recovery if the other driver has no insurance, too little, or can't be found. It does not mean unlimited recovery, and you still have to show the other driver was at fault and what your damages are.

Insurers must include it unless you waive it in writing

Section 11580.2(a) generally requires auto bodily injury liability policies issued in California to include UM coverage. The insured and the insurer can agree in writing, using specific statutory language, to delete it or to carry lower limits, but not below the Vehicle Code 16056 minimums. Under subdivision (m), UM must be offered with limits equal to your bodily injury liability limits, though insurers aren't required to offer UM above $30,000 per person and $60,000 per accident. Subdivision (n) says UM and UIM are offered as a single coverage, and UIM may be offered at higher limits. If you signed a waiver or a reduced-limits form when you bought the policy, it generally keeps applying at renewal, which is why checking matters.

How underinsured (UIM) coverage works

Section 11580.2(p) sets the UIM rules:

• What counts as underinsured. The at-fault vehicle is insured, but for less than the UM limits on the injured person's vehicle.
• Exhaust the other policies first. UIM doesn't apply until the bodily injury limits of every policy covering the vehicles that caused the injury have been paid out by judgment or settlement, and proof is given to your insurer.
• Offset. The most your UIM insurer owes is your UIM limit minus what was paid by or for anyone legally liable.

A hypothetical to show the math, not a prediction: if you carry $100,000 in UIM and the at-fault driver's insurer pays its full $30,000 limit, the most your UIM insurer could owe is $70,000, and only if your damages are at least that high. If your UIM limit equals the other driver's limit, UIM may add nothing. That's the practical reason higher limits matter.

Hit-and-run

If the at-fault driver can't be identified, section 11580.2(b) sets conditions for UM bodily injury coverage:

• Physical contact. The injury must arise out of physical contact between the unknown vehicle and you or the vehicle you were in.
• Report within 24 hours. You or someone for you must report the accident within 24 hours to the city police, or in unincorporated areas to the sheriff or the CHP.
• Sworn statement within 30 days. Within 30 days after that, you must file a statement under oath with your insurer that you have a claim against someone whose identity can't be determined, with supporting facts.

See my hit-and-run guide for more.

Uninsured motorist property damage (UMPD)

UM coverage under section 11580.2 doesn't cover property damage to your car (subdivision (c)(1)). Insurance Code section 11580.26 requires insurers to offer a separate property damage coverage:

• If you have collision coverage, it pays your collision deductible when you collide with an uninsured vehicle.
• If you don't have collision coverage, it pays damage to your insured car caused by an uninsured driver, up to the lesser of its actual cash value or $3,500.
• Conditions. Payment requires actual physical contact, and the uninsured driver must be identified or the vehicle identified by license number. The accident must be reported to your insurer within 10 business days.

So UMPD often won't help in a hit-and-run where the car is never identified. Collision coverage is what usually covers that.

Stacking and choosing limits (my advice, not a legal rule)

Some states let you "stack" UM limits from several vehicles or policies. California generally does not: section 11580.2(q) says limits for two or more vehicles or policies can't be added together or stacked. So the limit on the policy that applies is what you have. My suggestion is to carry UM/UIM limits at least equal to your own bodily injury liability limits, and higher if your insurer offers it and you can afford it. Ask your agent whether your umbrella policy offers UM/UIM. The statute doesn't require it for umbrella or excess policies, so don't assume it's there.

How to check your declarations page

1. Find your policy's declarations page (the summary page, usually in your insurer's app or online account).
2. Look for "Uninsured Motorist Bodily Injury" or "UM/UIM" and write down the per-person and per-accident limits.
3. Compare those to your "Bodily Injury Liability" limits. If UM is lower, or missing, ask your agent why and whether you signed a waiver.
4. Look for "Uninsured Motorist Property Damage" or a collision deductible waiver, and check whether you carry collision coverage.
5. Check for medical payments coverage too. Under section 11580.2(e), a policy can reduce UM damages by med-pay amounts paid or due.

If you need to make a UM/UIM claim

• Get your insurer's written consent before settling with anyone else. Under section 11580.2(c)(3), coverage doesn't apply if you settle with, or take to judgment, someone who may be liable without your insurer's written consent.
• Disputes go to arbitration. Under section 11580.2(f), if you and your insurer disagree about whether you're entitled to recover or how much, the policy must provide for arbitration before a single neutral arbitrator.
• Watch the two-year deadline. Under section 11580.2(i), within two years of the accident you generally must file suit against the uninsured motorist, reach an agreement with your insurer on the amount, or formally start arbitration by certified mail to the insurer.

How I can help

I handle injury cases on a contingency fee: no attorney's fee unless there is a recovery. Case costs may still apply, and every case is different. No outcome is guaranteed. If you've been hurt and aren't sure what coverage applies, send me the details and your declarations page.

Attorney advertising. This guide is general information about California law as of the date shown, not legal advice, and it may not reflect later changes or local rules. Reading it or contacting me does not create an attorney-client relationship. Results vary and no outcome is guaranteed. Better Call Vance, PC, Tyler Vance, CA Bar No. 318810, 3301 Michelson Drive, Suite 2107, Irvine, CA 92612.