Uninsured motorist coverage rules in Hawaii

If the driver who hit you had no insurance, too little insurance, or drove off without stopping, your own policy may be the only place left to look. In Hawaii that protection comes from uninsured motorist (UM) and underinsured motorist (UIM) coverage. The rules here differ from most states in two ways: Hawaii runs a no-fault system for medical bills, and it does not force you to carry UM or UIM at all. That combination shapes what you can recover, and when.

Hawaii does not require UM or UIM coverage

Hawaii law makes UM and UIM optional. What the law requires is an offer. When you first apply for or are issued an auto policy, the insurer has to give you the chance to buy both uninsured and underinsured motorist coverage.¹ You can turn it down, but only in writing, by signing a rejection in the spot the statute specifies.¹

Here is the part that catches people. Once you reject UM or UIM in writing, the insurer never has to offer it again on any renewal or replacement policy.¹ A signature you scribbled years ago, maybe without reading it, can still be the reason you have no coverage today. There is one opening. If you later make a material change to the policy, that new policy is not treated as a renewal, and the insurer owes you a fresh offer.¹ If you are not sure whether you rejected it, ask your insurer for the signed selection form in your file.

What counts as an uninsured or underinsured vehicle here

Hawaii defines these terms by statute. An uninsured motor vehicle is one with no bodily injury liability insurance in force at the time of the crash. It also includes a hit-and-run, meaning an unidentified vehicle that causes injury, as long as the crash is reported to the police or the proper authority within thirty days, or as soon as practicable after that.² That thirty-day reporting window matters. If a phantom driver hit you and you never filed a report, you can lose the UM claim before it starts. (For how to get a Hawaii crash report, see our Hawaii crash report guide.)

An underinsured motor vehicle is one that carries some liability insurance, but not enough to cover what the law says you are owed.² That is where UIM steps in, filling the gap between the at-fault driver's limits and your actual damages.

How much you can buy, and the stacking choice

You can buy UM and UIM up to, but not above, the bodily injury liability limits on your own policy.¹ Hawaii raised those minimum limits on January 1, 2026. Under Act 138 (2024), the floor moved from the old 20/40/10 to 40/80/20: $40,000 per person and $80,000 per accident for bodily injury, plus $20,000 for property damage.³¹ So a driver carrying only the new minimum can buy UM and UIM up to $40,000 per person and $80,000 per accident.

Hawaii also gives you a stacking decision most drivers never notice. When it makes the offer, the insurer has to present two options: one that lets you stack your UM and UIM coverage, and one that caps the coverage at your bodily injury limits without stacking.¹ Stacking usually costs more and pays more. Outside of that offered option, stacking is not allowed.¹ If you own more than one insured car, the stacked choice is worth a hard look.

UM and UIM sit on top of no-fault

Because Hawaii is a no-fault state, your own personal injury protection (PIP) pays your medical and rehabilitation costs first, regardless of who caused the crash, with a minimum of $10,000 in coverage.³ Your insurer has to pay or deny a PIP claim in writing within thirty days of proof of loss, and late payments carry 1.5 percent monthly interest.⁴

UM and UIM work differently. They cover what PIP does not, mainly pain and suffering and damages above your PIP and the at-fault driver's limits. But they behave like a tort claim, so Hawaii's no-fault threshold applies. You can recover for pain and suffering only once your case clears one of the statutory gates: death, a significant permanent loss of use of a part or function of the body, permanent and serious disfigurement, or PIP benefits that reach or exceed $5,000.⁵ Meet none of those and a UM or UIM claim for general damages does not get off the ground, the same as a claim against the other driver would not.

Your share of fault still counts

Hawaii follows modified comparative negligence with a 51 percent bar. You can recover even if you were partly to blame, and even if you were 50 percent at fault, but once your share of the fault is greater than the other side's, you recover nothing.⁶ The same rule applies inside a UM or UIM claim, so your insurer can argue you were mostly responsible in order to cut or defeat the payout, exactly the way the uninsured driver would have.

The deadline is not the one you think

Most Hawaii injury claims run on a two-year statute of limitations from the date of the crash.⁷ A UM or UIM claim is different, because it is a claim on your own insurance contract, not a lawsuit against the other driver. Hawaii has a separate statute for insurance-benefit claims. No suit on a motor vehicle insurance contract can be brought more than the later of: two years from the crash, two years after the last payment of benefits, two years after a final arbitration order, or, for underinsured motorist claims specifically, two years after payment of the liability coverage.⁸

That last trigger is easy to miss. Your UIM clock can start when the at-fault driver's insurer pays out its limits, which may fall well after the crash. It does not give you forever, and the safest course is to treat the two-year crash date as your hard deadline unless a lawyer confirms a later one applies. UM and UIM disputes in Hawaii are often sent to arbitration under the policy terms, which is why the statute counts time from a final arbitration order.⁸

If your insurer will not pay

A UM or UIM claim is adversarial in a way people do not expect. You are negotiating against your own insurer, and the money comes out of its pocket. Denials and lowball offers are common, and so are fights over your percentage of fault. If that happens, an attorney who handles Hawaii motor vehicle claims can press the claim through arbitration and, if the insurer acted in bad faith, pursue that as a separate matter. You can start with our Hawaii legal directory.

This is general information about Hawaii law, not legal advice.

Sources

Hawaii Revised Statutes § 431:10C-301, Required motor vehicle policy coverage (as amended by 2024 Act 138). https://data.capitol.hawaii.gov/hrscurrent/Vol09_Ch0431-0435H/HRS0431/HRS_0431-0010C-0301.htm
Hawaii Revised Statutes § 431:10C-103, Definitions (uninsured and underinsured motor vehicle). https://data.capitol.hawaii.gov/hrscurrent/Vol09_Ch0431-0435H/HRS0431/HRS_0431-0010C-0103.htm
Hawaii Department of Commerce and Consumer Affairs, Insurance Division, FAQ: Auto Insurance Minimum Limits (effective January 1, 2026). https://cca.hawaii.gov/wp-content/uploads/2026/01/Auto-Minimum-Limits-FAQs.pdf
Hawaii Revised Statutes § 431:10C-304, Obligation to pay personal injury protection benefits. https://data.capitol.hawaii.gov/hrscurrent/Vol09_Ch0431-0435H/HRS0431/HRS_0431-0010C-0304.htm
Hawaii Revised Statutes § 431:10C-306, Abolition of tort liability (no-fault threshold). https://data.capitol.hawaii.gov/hrscurrent/Vol09_Ch0431-0435H/HRS0431/HRS_0431-0010C-0306.htm
Hawaii Revised Statutes § 663-31, Contributory negligence no bar; comparative negligence. https://data.capitol.hawaii.gov/hrscurrent/Vol13_Ch0601-0676/HRS0663/HRS_0663-0031.htm
Hawaii Revised Statutes § 657-7, Damage to persons or property. https://data.capitol.hawaii.gov/hrscurrent/Vol13_Ch0601-0676/HRS0657/HRS_0657-0007.htm
Hawaii Revised Statutes § 431:10C-315, Statute of limitations. https://data.capitol.hawaii.gov/hrscurrent/Vol09_Ch0431-0435H/HRS0431/HRS_0431-0010C-0315.htm

Uninsured Motorist Coverage Rules in Hawaii