UM coverage pays your injury claim when the at-fault driver has no insurance or flees the scene. UIM coverage applies when that driver has insurance, but less than your own UM limits. Your carrier then pays the gap, not the full amount on top. Both live on your own policy under California Insurance Code 11580.2, and strict deadlines apply.
Uninsured motorist (UM) coverage and underinsured motorist (UIM) coverage are two halves of the same protection on your own auto policy. UM steps in when the other driver has nothing. UIM steps in when the other driver has something, but not enough. This article explains the difference between UM and UIM coverage in California, the offset rule that surprises most people, the hit-and-run rules, and the deadlines that can end a claim before it starts. It applies to California claims. Every case is different.
What is uninsured motorist (UM) coverage in California?
UM coverage pays for your injuries when the at-fault driver has no liability insurance at all. It also covers you in a hit-and-run when the driver is never identified. Under Insurance Code section 11580.2, every auto policy issued in California must include UM coverage unless you rejected it in a signed written waiver. Many people carry it without knowing it.
A UM claim is not a lawsuit against a stranger with no money. It is a claim on your own policy, for the coverage you already paid for. You still have to prove the other driver was at fault and prove your damages. In our practice we see uninsured drivers on the 10, the 210, and Arrow Highway every week, so this coverage does real work for local families.
Not sure what to do next? You can call Morales Law Firm for a free consultation before speaking with the insurance company, and there is no fee unless we win.
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What is underinsured motorist (UIM) coverage?
UIM coverage applies when the at-fault driver has liability insurance, but their limits are lower than your own UM limits. That is the legal definition in Insurance Code section 11580.2(p)(2). The other driver is “underinsured” only when their bodily injury limits are less than the UM limits on your policy.
Here is a common example from our office. A driver carrying the state minimum rear-ends you on the 57. Your medical bills and lost wages pass $80,000, but that driver’s policy pays out only $30,000. If you carry $100,000 in UM/UIM coverage, you can make a UIM claim with your own carrier for the rest of your damages, up to your limits. Without UIM coverage, collecting anything beyond the $30,000 usually means chasing a person who has no assets.
How is UIM different from UM? The offset rule
The big difference is the offset. A UM claim can pay up to your full UM limit. A UIM claim pays your UIM limit minus whatever the at-fault driver’s insurer already paid. Insurance Code section 11580.2(p)(4) caps your carrier’s exposure at your limit less that credit. In the example above, $100,000 in coverage minus a $30,000 payment leaves at most $70,000 from your own carrier. It is not $100,000 stacked on top.
Two more rules flow from this. First, if the other driver’s limits equal or exceed your UM limits, there is no UIM claim at all, even when your damages are far higher. Second, under section 11580.2(p)(3), the other driver’s policy generally must be exhausted by settlement or judgment before UIM coverage applies. Understanding these rules is a big part of knowing how much a car accident case is worth in California.
In our experience, one of the biggest mistakes injured people make after a crash with an underinsured driver is accepting the other insurer’s policy limits without telling their own UIM carrier first. That mistake can matter because settling without your carrier’s written consent can wipe out the UIM claim your premiums paid for. If you are dealing with this issue, save the settlement offer, the release, and every letter from both insurers, and do not sign anything before speaking with an attorney.
Does UM coverage apply to a hit-and-run in California?
Yes, but California adds strict conditions. Section 11580.2(b) requires physical contact between the unidentified vehicle and you or the car you occupied. A phantom driver who forces you off Arrow Highway without ever touching your car is a much harder claim. You must also report the crash to police within 24 hours and give your own insurer a sworn statement within 30 days.
Those two deadlines arrive fast when you are in the emergency room or arranging a rental car. Missing either one gives the carrier an argument to deny the whole claim. Call the police from the scene whenever you can, ask nearby businesses about cameras, and get your notice to the insurer in writing early. A short, accurate report beats a late, detailed one.
How much UM and UIM coverage should you carry?
Carry as much as you can reasonably afford, and match it to your liability limits. Since January 1, 2025, California’s minimum liability limits are $30,000 per person, $60,000 per accident, and $15,000 in property damage under Vehicle Code section 16056, and they are scheduled to rise again in 2035. Your insurer must offer UM/UIM limits up to your own liability limits, per the California Department of Insurance.
Remember the offset rule when you pick a number. If you carry minimum UM limits of 30/60 and the other driver carries the same minimum, UIM adds nothing. One ambulance ride and a night at a local hospital can pass $30,000 on their own. UM/UIM coverage is usually one of the cheaper lines on the policy, and it is the one that protects your family rather than the other driver.
What deadlines apply to UM and UIM claims?
Act within two years of the accident. Under Insurance Code section 11580.2(i), a UM or UIM claim generally dies unless, within two years, you filed suit against the uninsured driver, reached a written agreement with your carrier on the amount, or formally instituted arbitration. Simply reporting the claim or trading letters with an adjuster does not satisfy the statute.
The two-year window runs alongside the statute of limitations for a California car accident, but it is a separate trap. UIM claims are the classic example. Exhausting the other driver’s policy can take a year or more, and injured people assume the clock waits. It does not. We send a formal arbitration demand early in nearly every UM and UIM case to lock the deadline down.
What should you do after a crash with an uninsured driver?
The first week decides most UM and UIM fights. Here is the checklist we give our own clients:
- 1Call the police and get a report. For a hit-and-run, report within 24 hours. Ask for the report number before you leave.
- 2Get medical care the same day. Gaps in treatment become the carrier’s favorite argument against you.
- 3Photograph everything. Cars, plates, the intersection, your visible injuries, and the other driver’s license and insurance card if they stayed.
- 4Notify your own insurer promptly. UM claims have short notice rules, including the 30-day sworn statement for hit-and-runs.
- 5Do not sign a release or accept a settlement from the other insurer before understanding the consent rule.
- 6Keep every bill and record. Medical bills, wage records, mileage, and all letters from both carriers.
When should you call a lawyer?
Call before you give any statement or sign anything. Certain red flags mean the claim needs an attorney now: your own carrier delays for weeks or asks for a recorded statement and a broad medical authorization, the adjuster disputes fault or blames you, the at-fault driver’s insurer tenders its policy limits, your injuries need more than a few weeks of treatment, or the offer arrives before your treatment is finished. Deciding whether to accept the first settlement offer matters twice as much in a UIM case, because taking it the wrong way can forfeit the rest of your recovery.
Remember that in a UM or UIM claim, your own insurance company sits across the table. The adjuster may be friendly. The adjuster is not on your side.
How does Morales Law Firm handle UM and UIM claims?
We handle UM and UIM claims from our office at 151 W. Bonita Ave in San Dimas, serving Covina, Pomona, Glendora, La Verne, West Covina, and the rest of the San Gabriel Valley and Inland Empire. These claims usually resolve through arbitration rather than a jury trial, and the cases that end up in court are heard at Pomona Courthouse South or the San Bernardino Justice Center. You can read more about how we handle car accident claims on our practice page.
In a typical case we lock down the police report and coverage information, send the exhaustion and consent letters that protect the UIM claim, institute arbitration before the two-year deadline, and negotiate from documented damages. Francisco J. Morales, Esq. reviews every file personally, and clients get an honest read on how long a personal injury case takes before we start. The consultation is free, and there is no fee unless we win.
Frequently asked questions
Do I have to buy UM coverage in California?
No, but your insurer must offer it. Insurance Code 11580.2 requires UM coverage in every California auto policy unless you reject it in a signed written waiver. That waiver sticks through renewals. If you do not remember signing one, ask your agent for a copy of your declarations page and check.
Does UM coverage pay for damage to my car?
Only in a limited way. Uninsured motorist property damage under Insurance Code 11580.26 pays up to $3,500, and only when the uninsured driver or vehicle is identified and there was actual contact. Collision coverage, if you carry it, usually does the heavier lifting on vehicle repairs.
Can I settle with the other driver’s insurer before making a UIM claim?
Not without protecting the UIM claim first. The other driver’s limits generally must be exhausted, and settling without your own carrier’s involvement can destroy your UIM rights. Before you cash any check or sign any release, have an attorney confirm the consent and exhaustion steps are handled in writing.
Am I covered if an uninsured driver hits me while walking or biking?
Usually yes. UM coverage follows you as a person, not just your car. If an uninsured driver hits you in a crosswalk in San Dimas or on a bike on Bonita Avenue, you can typically claim under your own auto policy’s UM coverage, or under a resident family member’s policy in many situations.
Is a UM claim a lawsuit against my own insurance company?
No. It is a contract claim under your own policy, and disputes go to arbitration rather than a jury under Insurance Code 11580.2. You must still prove the other driver’s fault and your damages, the same as in a lawsuit. Formally instituting that arbitration within two years is what preserves the claim.
Can my passengers use my UM coverage?
Generally yes. Passengers occupying your insured vehicle are typically covered under your UM/UIM coverage if an uninsured or underinsured driver injures them. Their own auto policies may also apply, and which policy pays first depends on the policy language. An attorney can sort the layers in a free consultation.
Injured in a crash? Call or text Morales Law Firm at (626) 521-5402 for a free consultation. No fee unless we win.
Call or Text (626) 521-5402This article is for general educational purposes only and is not legal advice. Every case is different. Reading this article does not create an attorney-client relationship. If you were injured, speak with a qualified attorney about your specific facts and deadlines. Reviewed by Francisco J. Morales, Esq., California personal injury attorney, SBN 349235. About the author.
