Uninsured and underinsured motorist claims
About one California driver in six carries no insurance at all, and a great many more carry the state minimum. Your own UM and UIM coverage is what stands between that fact and your medical bills — and it comes with procedural traps that can void it.
UM and UIM are not the same thing
| Uninsured motorist (UM) | The at-fault driver had no liability insurance at all, or was an unidentified hit-and-run driver. Your UM limit responds to your damages. |
|---|---|
| Underinsured motorist (UIM) | The at-fault driver had insurance, but not enough. This is the one that is widely misunderstood. |
The practical consequence: carrying a UIM limit no higher than the state minimum is close to carrying nothing. It is the cheapest meaningful insurance most people can buy and the one most often declined.
Consent to settle — the step that destroys claims
Before accepting any settlement from the at-fault driver's insurer, you must obtain your own UIM insurer's written consent. Settling and signing a release without it can waive your underinsured claim entirely, because it destroys your insurer's right to pursue the at-fault driver.
This is a genuine trap. The at-fault insurer offers policy limits, it looks like good news, the release is signed, and the much larger UIM claim evaporates. Nobody involved has any duty to warn you.
It becomes a fight with your own insurer
A UM/UIM claim is a contract claim against your own insurer, and the relationship changes the moment the number gets large. The same company that was helpful about the rental car is now the adverse party valuing your injury.
California UM/UIM disputes usually go to arbitration rather than court, under the policy and Insurance Code section 11580.2. Arbitration is generally faster and the award is binding, and the arbitrator decides both fault and damages.
Your insurer does owe you a duty of good faith and fair dealing that it does not owe a third-party claimant. An unreasonable refusal to pay a claim it knows is owed can expose it to bad-faith liability beyond the policy limit — the lever that exists in a UM claim and not in a liability claim.
Proposition 213, if you were the uninsured one
It is a harsh rule and it is the law. There are exceptions worth checking: it does not apply to passengers, and it does not apply where the at-fault driver was convicted of driving under the influence. If you were uninsured at the time, say so early rather than late — it changes the strategy of the whole claim.
Questions people ask
If I use my own UM coverage, am I suing myself?
No. You are making a claim under a contract you paid premiums for, for a loss someone else caused. It is not an at-fault claim and should not be treated as one.
The other driver's insurer offered their policy limits. Can I just take it?
Not before you get your own underinsured motorist insurer's written consent, if you intend to make a UIM claim. Accepting and signing a release without consent can waive the UIM claim completely, because it destroys your insurer's right of recovery against the at-fault driver.
I have $100,000 of UIM and they had $30,000. Do I get $130,000?
No. California underinsured coverage is offset: your insurer is exposed for the difference, $70,000, for a total of $100,000. If your UIM limit is equal to or less than theirs, there is no UIM claim at all.
I did not have insurance when I was hit. Do I have a claim?
You can still recover medical expenses and lost earnings, but Proposition 213 generally bars non-economic damages for an uninsured driver injured in their own vehicle. The bar does not apply to passengers, and it does not apply where the at-fault driver was convicted of DUI.
Related
Reviewed October 2026 by Simon Aziz Budhwani, Esq., the attorney responsible for this site. Legal statements here name the California code section they rely on, so you can check them rather than trust them. This is information about the law in general, not advice about your situation.
Find out where you stand.
Tell us what happened and we will tell you honestly whether you have a claim worth bringing, what it is likely to involve, and how long it tends to take. The review is free and there is no fee unless there is a recovery.