Approximately 1 in 6 California drivers — about 17% of the 27 million registered vehicles in the state — carries no auto insurance whatsoever. That's nearly 4.5 million vehicles on California roads with zero liability coverage. When one of those drivers hits you, your ability to pay your medical bills, replace your car, and cover lost wages depends on one coverage that most people haven't thought about since they first bought their policy: Uninsured Motorist (UM) coverage.

What Uninsured Motorist Coverage Actually Does

UM coverage steps into the shoes of the at-fault driver when they don't have insurance. If an uninsured driver runs a red light, hits your car, and injures you, your UM policy pays:

  • Your medical bills and related treatment costs
  • Lost wages while you recover
  • Pain and suffering
  • Vehicle repair under UMPD (Uninsured Motorist Property Damage)

Underinsured Motorist (UIM) coverage works the same way when the at-fault driver has insurance but not enough to cover your actual damages — which in California happens constantly given how many drivers carry only the 30/60 state minimum.

The Limit Problem

Most California drivers who do have UM/UIM coverage don't have enough. Many have 15/30 or 25/50 limits — roughly matching the state minimum liability they're trying to protect against. But consider what a serious accident actually costs:

  • ER visit and initial treatment: $20,000–$50,000
  • Surgery or hospitalization: $50,000–$300,000
  • 6 weeks of lost wages (average California household): $15,000+
  • Follow-up rehab and PT: $10,000–$40,000

The industry recommendation is simple: match your UM/UIM limits to your liability limits. If you carry 100/300 liability, carry 100/300 UM/UIM. The additional cost is typically $30–$60 per year.

Hit-and-Run Drivers in California

California UM coverage applies to hit-and-run accidents where the driver fled the scene — but only if there is physical contact between vehicles. This is important: if a driver runs you off the road without touching you, UM may not apply. Some carriers offer broader hit-and-run coverage — worth asking about specifically.

💡 Bollinsure TipCalifornia law requires insurers to offer UM/UIM coverage and requires a written rejection to remove it. If you don't remember signing a rejection form, it's likely still on your policy — check your declarations page and confirm the limits match your liability coverage.

The $40 Decision

Increasing UM/UIM from 25/50 to 100/300 typically costs $30–$60 more per year on a California personal auto policy. That's about $0.08–$0.16 per day. Against the backdrop of 4.5 million uninsured vehicles sharing California roads with you, it's arguably the most straightforward value in insurance.