# What if the other driver does not have enough insurance? Canonical: https://californiapersonalinjurylaws.com/guides/underinsured-driver/ Reviewed by Andrew (Andy) R. Gillin; publisher reported approval on 2026-11-04. Original review date was not supplied. ## Short answer Your own underinsured motorist coverage may help. It can apply when the driver who hurt you has too little insurance. It does not always add both policy limits together. ## Hypothetical example A person’s losses are more than the other driver’s policy can pay. They check their own auto policy for help. ## How the rule works Underinsured motorist claims have rules about the other policy’s payment and your own limits. The coverage is not a simple extra pot of money. A release may affect the steps you can take next. ## Check the gap before you settle 1. **Other driver’s policy**: Check its limits and the proposed payment. 2. **Your own UIM policy**: Check limits, terms, and required steps. 3. **Covered loss**: Compare the proof and payments. Do not just add limits. This is a review path, not a formula for your recovery. The policy and legal steps still control. ## Two policies do not always add together Underinsured motorist coverage is often called UIM. It can matter when the at-fault driver’s injury limit is below your own UIM limit. The claim must still fit the law and policy. Do not add the two policy limits and treat the total as money you will get. Prior payments can reduce what remains. You must also prove the covered loss. Limits are ceilings, not a case value. The amount of harm is a separate issue. Read [what affects an injury claim’s value](https://californiapersonalinjurylaws.com/guides/case-value/). For the policy labels, see [how standard policy limits work](https://californiapersonalinjurylaws.com/guides/california-auto-insurance-minimums/). Sources: [Insurance Code § 11580.2 — Uninsured motorist coverage](https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=INS§ionNum=11580.2.); [California Department of Insurance — Automobile insurance guide](https://www.insurance.ca.gov/01-consumers/105-type/95-guides/01-auto/auto101.cfm) ## Review the next step before a release Keep the other policy’s offer, its limits, your own policy, and all proposed releases together. Ask what payment or proof is needed before the UIM claim can move forward. Macri explains why a rule for one type of motorist coverage cannot simply be copied to another. It is not a reason to sign a release before checking your own claim. Before you sign, read [what a settlement release gives up](https://californiapersonalinjurylaws.com/guides/settlement-release/). If there is no insurance at all, compare [uninsured motorist coverage](https://californiapersonalinjurylaws.com/guides/uninsured-driver/). Sources: [Insurance Code § 11580.2 — Uninsured motorist coverage](https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=INS§ionNum=11580.2.); [Hartford Fire Ins. Co. v. Macri (1992) 4 Cal.4th 318](https://law.justia.com/cases/california/supreme-court/4th/4/318.html) ## What can change the answer The limits and terms matter. Money paid under one policy can affect what the other pays. Some steps must happen before you settle with the other driver. ## A useful next step Check your own policy before you sign a release. Ask about the steps and time limits for this type of claim. ## How long does it take to find out the coverage limits? There is no fixed answer for every claim. Records, policy terms, and who may be responsible can affect the review. Ask what is still missing and which deadlines apply. ## Does a low policy limit prove my case is worth that amount? No. A limit concerns what a policy may pay. Value concerns the loss you can prove and the rules that apply. Other payment sources may also need review. ## Which papers help with a coverage review? Keep your coverage page, the full policy, letters about the other driver’s limits, offers, and releases. Note any dates in the letters. Ask what else is needed. ## Court decisions behind this answer ### Hartford Fire Ins. Co. v. Macri (1992) 4 Cal.4th 318, pp. 323–329. No insurance and too little insurance are different problems. The court held that some coverage rules differ too. Limit: Read the current law and policy. Do not assume the same steps apply to both kinds of coverage. Source: https://law.justia.com/cases/california/supreme-court/4th/4/318.html ## Sources - [Insurance Code § 11580.2 — Uninsured motorist coverage](https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=INS§ionNum=11580.2.) - [California Department of Insurance — Automobile insurance guide](https://www.insurance.ca.gov/01-consumers/105-type/95-guides/01-auto/auto101.cfm) - [Hartford Fire Ins. Co. v. Macri (1992) 4 Cal.4th 318](https://law.justia.com/cases/california/supreme-court/4th/4/318.html) - [Civil Code § 3333 — Compensation for harm](https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=CIV§ionNum=3333.) General information, not legal advice.