If the driver who hit you in California had no insurance, or not enough, your claim does not end. It moves to your own policy. The coverage that pays is called uninsured motorist coverage, UM for short, and its cousin underinsured motorist coverage, UIM. Nearly every California driver has it, because an insurer cannot sell you a policy without offering it and can only leave it off if you rejected it in writing. The catch is that your own insurance company now sits on the other side of the table, it treats the claim exactly the way the other driver’s insurer would have, and the Uninsured Motorist Act has deadlines and paperwork rules that end claims when they are missed. This is what the law requires, what your policy pays, and where people lose these cases.
First, why so many drivers are uninsured, and why “the minimum” matters
California’s required liability insurance was 15/30/5 for more than fifty years: $15,000 for one injured person, $30,000 for everyone injured in the crash, $5,000 for property damage. Those numbers were set in 1967. On January 1, 2025, Senate Bill 1107, the Protect California Drivers Act, raised them to 30/60/15, and the law schedules another increase to 50/100/25 in 2035.
Two things follow. First, a large share of the drivers on the 118 and the 101 still carry the state minimum, and if you were hit by one of them after a serious injury, $30,000 is gone before the emergency room bill is paid. That is an underinsured driver, and your UIM coverage is what fills the gap. Second, the Department of Insurance and industry estimates have put California’s uninsured driver rate somewhere around one in six for years. One in six is not a rare event. It is a Tuesday.
What your insurer was required to offer you
The Uninsured Motorist Act is Insurance Code sections 11580.2 through 11580.5. Under section 11580.2, every auto liability policy issued in California has to include uninsured motorist bodily injury coverage unless you, the named insured, rejected it or chose lower limits in a signed writing. If there is no signed waiver in your file, the coverage is in your policy whether or not the declarations page shows it.
The insurer has to offer UM limits at least equal to your liability limits, up to the amounts stated in the statute. If you bought $100,000 of liability coverage, you should have been offered $100,000 of UM. People routinely find out after a crash that an agent “saved them money” by dropping UM to the minimum, with a signature they do not remember. Ask your insurer for the signed UM selection form. If they cannot produce one, your UM limits are your liability limits.
Underinsured motorist coverage, UIM, is part of the same coverage in California. It applies when the other driver has insurance but the limits are lower than your UIM limits.
What the coverage pays
UM and UIM pay what the at-fault driver would have owed you if that driver had been properly insured: medical bills, lost income, and compensation for pain and the loss of your normal life, up to your UM limit.
There is one rule that catches almost everyone with UIM. Under section 11580.2, subdivision (p)(4), your insurer’s maximum payment is your UIM limit minus what the at-fault driver’s insurer paid. If you carry $100,000 of UIM and the other driver’s insurer pays its $30,000 limit, your own company’s exposure is $70,000, not $100,000. California is an “offset” state. When you are deciding how much UM/UIM to buy, that is the arithmetic that matters, and it is why we tell every client to carry as much UM/UIM as they carry in liability, and more if they can.
UM also covers you as a pedestrian, as a passenger in someone else’s car, and in a hit-and-run, subject to the rules below. It follows you, not just your car.
Hit-and-run: three requirements people miss
If the driver who hit you took off and was never identified, your claim is a UM claim against your own policy, but section 11580.2, subdivision (b), adds conditions that are strictly enforced.
There has to have been physical contact between the unknown vehicle and you or your vehicle. If a car cut you off and you swerved into a wall without being touched, California does not treat that as a hit-and-run UM claim, however unfair that is. Paint transfer, a dented quarter panel and a damaged mirror are how we prove contact when the other car is gone.
The accident has to be reported to the police or the CHP within 24 hours.
A sworn statement that you have a claim against an unknown person, with the facts, has to be filed with your insurer within 30 days.
Miss any of the three and the insurer will deny the claim and the law will let it. The 24-hour police report is the one most people miss, usually because the damage looked minor at the roadside and the pain did not start until the next morning. Call the police anyway.
The two-year deadline, and why a letter is not enough
For a UM claim, section 11580.2, subdivision (i), requires one of three things within two years of the accident: a lawsuit filed against the uninsured driver, a written agreement with your insurer on the amount owed, or a formal demand for arbitration sent to your insurer by certified mail. A phone call does not satisfy it. A letter from a lawyer that does not formally demand arbitration does not satisfy it; the Court of Appeal said so in Allstate v. Gonzalez. Treatment that is still ongoing at the two-year mark is not an excuse. The demand goes out before the deadline regardless.
UIM claims have a different clock. Because you first have to exhaust the at-fault driver’s policy, the UIM claim has to be brought within a reasonable time after that policy pays. “Reasonable” is not a date on a calendar, which is why we send the UIM notice the day the underlying claim is opened and the demand the day the underlying limits are tendered.
Exhaustion: do not settle the other driver’s policy without telling your insurer
Before your UIM coverage pays anything, the at-fault driver’s insurer has to pay its full policy limits. And before you accept those limits, your own insurer gets notice and a chance to object, because once you release the at-fault driver, your insurer loses its right to go after that driver for what it pays you. Settling the underlying claim without that notice is one of the few ways to forfeit UIM coverage entirely. It is a step we handle in writing, every time.
Your own insurer is not your friend in this claim
People assume the company they have paid for years will treat a UM claim differently than a stranger’s insurer would. It does not. The adjuster will ask for a recorded statement, ask to see your medical history going back years, send you to a doctor the insurer chooses, and argue that your injuries are old, minor or unrelated. Everything you would be told not to do with the other driver’s insurer applies here. California law does require your insurer to deal with you in good faith, and an insurer that unreasonably delays or lowballs a UM claim can be held liable beyond the policy limit, but that is leverage, not protection. The protection is handling the claim correctly from day one.
If the claim does not settle, a UM/UIM dispute is decided by arbitration, not a jury trial, under the policy and section 11580.2. The arbitrator decides what the at-fault driver would have owed you. The preparation is the same as for trial.
What a UM/UIM claim looks like in practice
A client is rear-ended on Topanga Canyon Boulevard. The other driver has the old 15/30 minimum. The client has a herniated disc, two months of physical therapy and an injection, and carries $250,000 of UIM. The other driver’s insurer tenders $15,000. We give our client’s insurer written notice of the tender and the right to object, the insurer consents, the $15,000 is accepted, and the UIM claim is presented for the remaining value. The insurer’s exposure is $235,000. The claim is documented like any other injury claim, with records, bills, wage proof and the treating doctor’s opinion on future care, and it settles or goes to arbitration.
Key points
If the other driver had no insurance, or too little, your own UM/UIM coverage pays, up to your limit and, for UIM, minus what the other driver’s insurer paid.
Your insurer had to offer UM equal to your liability limits. If there is no signed waiver in your file, you have it at those limits.
Hit-and-run claims need physical contact, a police report within 24 hours, and a sworn statement to your insurer within 30 days.
A UM claim must be preserved within two years by suit, written agreement or a certified-mail arbitration demand. A letter is not enough.
Never settle the at-fault driver’s policy without written notice to your own insurer first.
Frequently asked questions
Will a UM claim raise my rates? California’s Proposition 103 rating rules bar insurers from surcharging you for an accident you were not principally at fault for. A UM claim arising from someone else’s fault should not raise your premium.
The other driver has insurance but the company will not confirm limits. How do I know if I need UIM? California requires the other driver’s insurer to disclose the policy limits in writing within 30 days of a written request that includes the information the statute calls for. We send that request at the start of every case.
I was a passenger. Whose UM applies? The policy on the car you were in applies first. If you have your own auto policy, it may apply next. Both are checked.
Do I need a lawyer if it is my own insurance company? The deadlines in this article are where most of these claims die, and your insurer is under no obligation to remind you of them. A UM/UIM claim is handled on the same contingency fee as any other injury claim: nothing up front, nothing unless we recover for you.
Manoukian Law Firm, P.C., Chatsworth, California. Free consultation. No fee unless we win. Past results do not guarantee a similar outcome.
