Updated July 2026
What Is Uninsured and Underinsured Motorist Coverage Insurance?
Uninsured motorist coverage (UM) pays your medical bills, lost wages, and pain-and-suffering damages when an at-fault driver has no liability insurance. Underinsured motorist coverage (UIM) kicks in when the at-fault driver's liability limits are too low to cover your full claim. Both coverages protect you from out-of-pocket losses that would otherwise fall on you when another driver's insurance is absent or inadequate. Florida law does not mandate UM/UIM, so carriers exclude it unless you explicitly add it.
- You're stopped at a red light. The driver behind you has no insurance and rear-ends you at 35 mph. You have $18,000 in medical bills and $6,000 in lost wages. The at-fault driver has no assets and no liability coverage. Your UM coverage pays the full $24,000 up to your policy limit. Without UM, you sue the driver personally and likely collect nothing.
- A driver with Florida's minimum $10,000 bodily injury liability runs a stop sign and T-bones your car. You suffer a broken pelvis with $85,000 in medical costs and $20,000 in lost income. The at-fault driver's insurer pays their $10,000 limit. Your UIM coverage pays the remaining $95,000 up to your UIM limit. Without UIM, you absorb $95,000 in losses the other driver cannot pay.
- A driver runs a red light, strikes your vehicle, and flees the scene. You sustain $32,000 in medical expenses and cannot identify the driver. Your UM coverage treats the unknown driver as uninsured and pays your claim up to your UM limit. Without UM, you file under your health insurance and pay the deductible and coinsurance yourself.
Who Needs Uninsured and Underinsured Motorist Coverage Insurance?
Carry UM/UIM if you cannot afford to pay your own medical bills and lost wages after a serious accident. Florida's high uninsured driver rate and low minimum liability limits mean the at-fault driver often has no coverage or insufficient coverage to pay your claim. If you have significant assets, a mortgage, or dependents who rely on your income, UM/UIM is the only coverage that protects you when the other driver's insurance fails.
Compare your UM/UIM limit to your health insurance deductible and out-of-pocket maximum. If a $30,000 injury would bankrupt you or force you into debt, carry UM/UIM at least equal to your liability limit. If your health plan and savings can absorb a $50,000 loss, you can decline UM or select a lower limit to save $10–$15/month.
How Much Does Uninsured and Underinsured Motorist Coverage Insurance Cost?
UM/UIM coverage typically adds $8–$18 per month to a Florida auto policy, or roughly $96–$216 annually, depending on the limits you select and your driving history.
- Selected UM/UIM limits—higher limits cost more, but the incremental cost from $25,000 to $100,000 is often under $10/month.
- Your county's uninsured driver rate—Miami-Dade and Broward counties have higher uninsured rates, which can increase UM premiums slightly.
- Stacking versus non-stacking coverage—stacked UM multiplies your limit by the number of vehicles on your policy, roughly doubling the premium.
- Your at-fault claim history—carriers price UM based partly on your likelihood of filing any claim, not just UM claims.
- Bundling with PIP or collision—some carriers discount UM when you carry personal injury protection or collision coverage on the same policy.