By John Stevenson
Uninsured vs. Underinsured Motorist Coverage Costs: What Drivers Should Compare
Uninsured motorist coverage and underinsured motorist coverage protect you from a risk you cannot control: another driver who has no insurance or not enough insurance to pay for serious losses after a crash.
The cost of UM/UIM depends on your state, selected limits, insurer, driving profile, policy structure, and whether property damage or stacked coverage is available. Instead of choosing based on one generic average, compare the line-item price at different limit levels.
For a simple coverage comparison, review uninsured vs. underinsured motorist coverage.
Understanding Uninsured Motorist Coverage
Uninsured motorist coverage, often shortened to UM, usually applies when the at-fault driver has no valid auto liability insurance. Depending on state and policy language, UM can also apply to certain hit-and-run situations. UM bodily injury may help with covered medical bills, lost income, pain-related damages, and other eligible injury losses.
UM property damage, sometimes called UMPD, is different. It may help repair your vehicle after an uninsured-driver crash, but it is not available the same way in every state. In some cases, collision coverage may be the coverage that repairs your vehicle instead.
UM may help when…
- The at-fault driver has no valid liability policy.
- A qualifying hit-and-run is covered under your state and policy rules.
- You or covered passengers have eligible injury-related losses.
- UMPD is available and selected for vehicle damage.
UM may not cover…
- Your own vehicle damage unless UMPD or collision applies.
- Every hit-and-run scenario automatically.
- Losses above your selected UM limits.
- Claims that fail documentation or state-specific requirements.
Understanding Underinsured Motorist Coverage
Underinsured motorist coverage, often shortened to UIM, is different from UM. UIM usually applies when the at-fault driver has insurance, but their liability limits are too low to cover your eligible injury losses.
For example, a driver may carry only state minimum bodily injury limits. If multiple people are injured or medical costs exceed that low limit, the other driver’s policy may run out quickly. UIM can help fill part of the gap, up to your own selected limits and subject to state rules, offsets, exclusions, and policy terms.
UIM may help when…
- The at-fault driver has insurance but too little liability coverage.
- Your covered losses exceed the other driver’s available limit.
- Multiple injured people must share one low liability limit.
- Your state and policy allow UIM to respond after the other policy pays.
Questions to ask
- Does UIM offset against the other driver’s limit?
- Do I need insurer consent before settling with the other driver?
- Are my limits stacked or non-stacked?
- Does UIM cover only injuries or also vehicle damage?
For a deeper explanation, read uninsured and underinsured coverage explained.
Comparing UM vs. UIM Costs the Right Way
The most useful comparison is not “UM costs X and UIM costs Y.” The better question is: what does your insurer charge for each limit level on your exact policy?
Bankrate reports that adding UM coverage may cost about $5 to $25 per month, depending on your profile and insurer [3]. That is a helpful range, but it is still only a general estimate. Your actual price may be higher or lower depending on state risk, policy limits, vehicle, drivers, and insurer pricing.
| Quote Version | What It Shows | Why It Helps |
|---|---|---|
| No UM/UIM, if allowed | Your baseline price without the coverage. | Shows the true line-item cost if your state allows rejection. |
| Lower UM/UIM limits | The cost of basic protection. | Useful if budget is tight but you do not want to reject protection completely. |
| UM/UIM matching liability limits | The cost of protecting yourself closer to the level you protect others. | Often a practical comparison point for households and commuters. |
| Higher UM/UIM limits | The cost of stronger protection for serious injury losses. | Useful for drivers with passengers, savings, income, or long commute exposure. |
For more price context, compare this guide with cost of uninsured motorist coverage.
UM/UIM Cost Compass
Use this four-step method before accepting, lowering, or rejecting UM/UIM coverage.
- Check your state rules.
- Quote multiple limits.
- Review stacking.
- Compare with your savings risk.
Read your declarations page
Look for UMBI, UIMBI, UMPD, stacked or non-stacked language, selected limits, and any rejection or lower-limit forms.
Compare UM/UIM to bodily injury liability
Many drivers start by asking what it costs to match UM/UIM limits to bodily injury liability limits, where state rules allow it.
Ask about stacking
In some states, stacked coverage can combine limits across vehicles or policies. It may cost more, but it can increase available protection.
Stress-test your finances
Ask how long you could cover medical bills, lost income, transportation, and recovery costs if the at-fault driver had no usable coverage.
State Rules Can Change the Cost and the Decision
UM/UIM is heavily state-specific. Some states require uninsured motorist coverage, some require insurers to offer it, and others allow rejection or lower-limit selection through written forms. That means two drivers with identical cars and records may see different UM/UIM choices simply because they live in different states.
NAIC reports that IRC estimated 15.4% of motorists were uninsured in 2023, with state uninsured motorist rates ranging from 5.7% in Maine to 28.2% in Mississippi [1]. In Florida, for example, state law says uninsured motorist coverage limits shall not be less than the bodily injury liability limits purchased, unless the named insured selects a lower limit that complies with the company’s rating plan [4].
Ask your insurer
- Is UM/UIM required, optional, or rejectable in my state?
- Can I select limits lower than my bodily injury liability?
- Does rejection require a signed form?
- Can I stack limits across vehicles?
Ask your state regulator
- What are the current UM/UIM rules?
- Is UMPD available or separate?
- Do hit-and-run rules apply differently?
- Where can I verify consumer guidance?
For limit-focused guidance, see essential uninsured motorist coverage limits.
UM/UIM Cost Factors to Review
UM/UIM pricing is affected by more than one factor. Your insurer may consider state rules, claim trends, selected limits, household drivers, location, and whether the coverage includes bodily injury only or also property damage protection.
| Cost Factor | How It Can Affect Premium | Question to Ask |
|---|---|---|
| Selected limits | Higher UM/UIM limits usually cost more but provide more protection. | What is the monthly difference between each available limit level? |
| State uninsured rate | States with more uninsured drivers may create higher claim exposure. | How does my state or ZIP code affect UM/UIM pricing? |
| Stacking option | Stacked coverage may increase available limits and may increase cost. | Is my policy stacked or non-stacked? |
| UMPD availability | Vehicle damage coverage may be separate, unavailable, or handled through collision. | Does my policy include uninsured motorist property damage? |
| Driving and household profile | Drivers, claims history, location, and vehicle use can affect overall policy pricing. | Which rating factors are influencing my quote most? |
Real-World UM vs. UIM Scenarios
These examples are simplified and educational. Actual claim outcomes depend on state law, policy language, fault, damages, documentation, limits, and insurer handling.
| Scenario | Which Coverage May Matter | What to Watch |
|---|---|---|
| You are hit by a driver with no insurance. | UM bodily injury may help with covered injury losses. UMPD or collision may handle vehicle damage, depending on state and policy. | Police report, proof of no insurance, hit-and-run rules, and claim deadlines. |
| You are hit by a driver with low liability limits. | UIM may help if your covered losses exceed the at-fault driver’s available liability limits. | Offset rules, consent-to-settle rules, and how your state calculates UIM recovery. |
| Multiple passengers are injured. | UM/UIM limits may be shared across covered people, depending on policy and limit structure. | Per-person and per-accident limits, stacked coverage, and settlement allocation. |
| Your parked car is damaged by an uninsured driver. | UMPD may help if available and selected. Collision may help if you carry it. | Deductible, proof requirements, and whether UMPD applies to property damage in your state. |
For broader risk context, review financial risks of uninsured motorist coverage gaps.
Common Misconceptions About UM/UIM
“My liability covers me.”
Liability mainly protects you when you injure someone else or damage their property. It does not replace UM/UIM protection for your own injury losses caused by another uninsured or underinsured driver.
“Health insurance solves it.”
Health insurance may help with medical bills, but it may not cover lost wages, pain-related losses, passengers, deductibles, or every accident-related cost.
“Minimum limits are enough.”
Minimum limits may satisfy law, but serious injuries can exceed low limits quickly, especially when several people are injured.
Quick Auto Insurance Cost Estimator
This tool gives a rough educational estimate based on age, driving record, vehicle type, and coverage level. It is not a binding quote and does not replace an insurer’s official rate.
Use it to compare how different coverage choices may change a monthly estimate, then enter your ZIP code to request real quote options.
This calculator is only an educational estimate. Final pricing depends on state, insurer, driver profile, vehicle, coverage limits, discounts, fees, and underwriting.
FAQ: Uninsured vs. Underinsured Motorist Coverage Costs
What is the difference between UM and UIM?
UM usually applies when the at-fault driver has no valid insurance. UIM usually applies when the at-fault driver has insurance, but their liability limits are too low to cover your eligible losses.
How much does uninsured motorist coverage cost?
Costs vary by state, insurer, driver profile, and selected limits. Bankrate reports that adding UM coverage may cost roughly $5 to $25 per month, but your real cost should come from a quote using your own policy details.
Does UM/UIM cover damage to my car?
Not always. UM/UIM bodily injury usually focuses on injury-related losses. Vehicle damage may require UMPD, collision, or another coverage depending on state rules and your policy.
Should UM/UIM limits match my liability limits?
Many drivers compare matching limits because it balances the protection they give others with the protection they keep for themselves. The right choice depends on budget, state rules, savings, income, and household risk.
Can I reject UM/UIM coverage?
In some states, yes, but rejection may require a written form. In other states, UM/UIM may be required or offered under specific rules. Ask your insurer and state insurance department what applies where you live.
Can a UM/UIM claim affect my rate?
It can, depending on state rules, insurer practices, claim facts, and your claim history. Ask how UM/UIM claims are treated at renewal before filing for a small loss.
Final Takeaways
Uninsured and underinsured motorist coverage can be a valuable protection layer because you cannot control whether another driver has enough insurance. With more than one in seven drivers estimated to be uninsured nationally in 2023, UM/UIM is worth reviewing before you reject or lower it.
The smartest move is to compare real quote versions: lower limits, matching limits, and stronger limits. Look at the monthly difference, not just the base premium. If the extra cost is reasonable, higher UM/UIM limits may reduce a serious financial gap after a crash.
References
- National Association of Insurance Commissioners, Uninsured Motorists topic page citing Insurance Research Council 2023 uninsured motorist estimate. Source↩
- Insurance Research Council, Uninsured and Underinsured Motorists: 2017–2023. Source↩
- Bankrate, Uninsured Motorist Coverage cost overview. Source↩
- Florida Statutes, Section 627.727, Motor vehicle insurance; uninsured and underinsured vehicle coverage. Source↩
- Bankrate, Underinsured Motorist Coverage overview. Source↩