By Jane Taylor
Uninsured Motorist Coverage Costs: How UM and UIM Pricing Really Works
Uninsured motorist coverage and underinsured motorist coverage exist because another driver may have no insurance or not enough insurance to pay for serious injuries. Even if you drive carefully, you cannot control the coverage carried by the person who hits you.
According to NAIC, the Insurance Research Council estimated that 15.4% of motorists, about one in seven drivers, were uninsured in 2023. State rates vary widely, which is one reason UM/UIM pricing and requirements can look very different depending on where you live.
For a quick side-by-side explanation, start with uninsured vs. underinsured motorist coverage.
UM vs. UIM: What They Cover in Plain English
Uninsured motorist coverage, often called UM, usually applies when the at-fault driver has no valid liability insurance. Underinsured motorist coverage, often called UIM, usually applies when the at-fault driver has liability insurance, but their limits are too low for the covered injury losses.
UM and UIM most commonly focus on bodily injury losses, such as medical bills, lost income, and certain other injury-related damages. In some states, uninsured motorist property damage may be available separately. Your declarations page may show terms such as UMBI, UIMBI, or UMPD.
UM may help when…
- The at-fault driver has no valid auto liability insurance.
- A qualifying hit-and-run applies under your state and policy rules.
- You or covered passengers have eligible injury-related losses.
- UMPD is available and selected for qualifying vehicle damage.
UIM may help when…
- The at-fault driver has insurance but low liability limits.
- Your covered losses exceed the other driver’s available coverage.
- Multiple injured people must share the at-fault driver’s limit.
- Your policy and state rules allow UIM to respond after the other limit is known.
For a broader explanation, see uninsured and underinsured coverage explained.
Why UM/UIM Can Matter More Than Drivers Expect
Many drivers assume the other driver’s liability insurance will pay after a crash. That can fail in two ways: the driver may have no insurance, or the driver may carry only minimum limits that are too low for a serious injury claim.
NAIC reports that IRC estimated 15.4% of U.S. motorists were uninsured in 2023, with state rates ranging from 5.7% in Maine to 28.2% in Mississippi. III reports the same national 2023 uninsured motorist estimate and notes that most states saw increasing uninsured motorist trends from 2017 to 2023.
No-insurance risk
UM can help when the at-fault driver has no valid policy or when certain hit-and-run rules apply.
Low-limit risk
UIM can help when the other driver has insurance, but the available limit does not cover the eligible losses.
Household risk
Passengers, family members, pedestrians, or cyclists may also be affected depending on policy language and state rules.
What Drives the Cost of UM and UIM Coverage?
UM/UIM is usually priced with many of the same risk factors used for your overall auto policy. But the coverage is especially sensitive to state rules, local uninsured-driver exposure, selected limits, and whether stacking or property damage coverage is available.
| Cost Factor | How It Can Affect Price | What to Ask Your Insurer |
|---|---|---|
| State rules | Some states require UM/UIM, some require it to be offered, and others allow different rejection or lower-limit rules. | Is UM/UIM required, optional, or rejectable in my state? |
| Uninsured-driver rate | Higher uninsured-driver exposure can influence claim expectations and pricing. | How does my state or ZIP code affect UM/UIM pricing? |
| Selected limits | Higher UM/UIM limits generally cost more but provide more protection. | What is the monthly difference between my current limit and the next higher limit? |
| Stacking | In some states, stacking can combine limits across vehicles or policies, increasing available protection and sometimes cost. | Is my policy stacked or non-stacked, and what does that change? |
| UMPD availability | Vehicle damage coverage for uninsured-driver accidents may be separate and state-specific. | Do I have uninsured motorist property damage or only bodily injury coverage? |
| Driver and household profile | Driving record, claims history, garaging location, and household drivers can affect overall policy pricing. | Which part of my profile is affecting the quote most? |
How Much Does Uninsured Motorist Coverage Usually Cost?
Exact cost depends on your state, driver profile, vehicle, insurer, policy structure, and chosen limits. Still, many drivers find UM/UIM to be a relatively modest add-on compared with the overall policy. Bankrate reports that adding UM coverage may cost roughly $5 to $25 per month, depending on the driver profile and insurer.
Generic estimates are useful for context, but they should not replace a real quote. The cleanest method is to ask your insurer for three versions of the same policy: without UM/UIM if allowed, with matching lower limits, and with stronger limits. Then compare the monthly and full-term difference.
| Quote Scenario | What It Shows | Best Use |
|---|---|---|
| Current policy limits | Shows your baseline premium and current protection level. | Use as the starting point before changing limits. |
| UM/UIM matching liability limits | Shows the cost of protecting yourself closer to the same level you protect others. | Useful for households that want balanced coverage. |
| Higher UM/UIM limits | Shows whether stronger protection costs only a small amount more. | Useful for commuters, families, and drivers with passengers. |
| UMPD or collision comparison | Shows whether vehicle damage is handled through UM property damage, collision, or both. | Useful if you are worried about repair costs after an uninsured-driver crash. |
For more price-focused information, review cost of uninsured motorist coverage.
How to Pick UM/UIM Limits
The best limit is not the same for every driver. A practical approach is to compare UM/UIM limits against your liability limits, savings, income, passengers, commute, and state rules.
- Start with your liability limits.
- Quote at least two UM/UIM levels.
- Ask about stacking and offsets.
- Check rejection forms.
Check your current declarations page
Look for UMBI, UIMBI, UMPD, stacking status, limits per person/per accident, and any rejection or lower-limit forms.
Compare against bodily injury liability
Many drivers start by asking whether UM/UIM should match their bodily injury liability limits, where state rules and insurer options allow.
Stress-test your finances
Ask how long your emergency fund could cover bills if a crash caused medical costs, lost income, or long recovery time.
Quote multiple limit levels
Compare options such as $50k/$100k, $100k/$300k, and $250k/$500k if available, then review the monthly difference.
UM/UIM Limits and State Rules: Why the Fine Print Matters
UM/UIM rules are heavily state-specific. Some states require the coverage, some require insurers to offer it, and others allow you to reject or select lower limits in writing. In Florida, for example, state law says uninsured motorist limits shall not be less than the bodily injury liability limits purchased by the named insured, unless a lower limit complying with the company’s rating plan is selected.
This is why the forms matter. A driver may think they have strong UM/UIM protection, but the policy may show lower selected limits, non-stacked coverage, or a prior rejection. Ask your insurer for copies of any UM/UIM selection or rejection forms if you are not sure what you chose.
Ask about state rules
- Is UM/UIM required or optional in my state?
- Can I reject UM/UIM, and must rejection be in writing?
- Can I choose limits lower than bodily injury liability?
- Does my state allow stacked coverage?
Ask about policy mechanics
- Does UIM pay above the other driver’s limit or offset against it?
- Does UM cover hit-and-run claims in my state?
- Is vehicle damage handled by UMPD, collision, or both?
- Are pedestrians or cyclists covered under certain situations?
For limit-focused guidance, see essential uninsured motorist coverage limits.
UM/UIM Cost vs. Potential Claim Risk
The monthly cost of UM/UIM can feel like another add-on, but the claim risk can be significant if the at-fault driver has no insurance or only minimum limits. A serious injury claim can involve emergency treatment, follow-up care, lost wages, transportation costs, and long recovery time.
Lower-cost decision
Drivers sometimes keep only required limits to reduce premium, but this can leave gaps after a serious crash.
Balanced decision
Many households quote UM/UIM limits that match their bodily injury liability limits for a more balanced policy.
Stronger-protection decision
Families, frequent commuters, and drivers with passengers may compare higher limits to reduce severe out-of-pocket exposure.
For a broader protection discussion, review financial risks of uninsured motorist coverage gaps.
Can a UM/UIM Claim Raise Your Rates?
It can, depending on the insurer, state rules, claim facts, claim frequency, and your overall policy history. Some states restrict how not-at-fault claims are treated. Other insurers may still consider claim frequency or total risk when setting future premiums.
Before filing for a small loss, ask how the claim could affect renewal and whether a deductible, threshold, or documentation requirement applies. UM/UIM is designed for meaningful losses, especially injury-related claims where the other driver has no coverage or not enough coverage.
After an uninsured-driver crash
- Get medical help when needed.
- Call police when appropriate, especially for hit-and-run or no-insurance situations.
- Gather photos, witness details, and vehicle information.
- Notify your insurer quickly and ask about UM/UIM deadlines.
- Keep bills, wage records, estimates, and claim letters.
Claim questions to ask
- What proof is required?
- Does a police report affect eligibility?
- Are there consent-to-settle rules?
- How does the insurer calculate UIM after the other policy pays?
- Could this claim affect renewal?
For step-by-step claim context, see uninsured motorist claim basics and steps.
Composite Driver Scenarios
These are generalized examples based on common UM/UIM decision points. They are not specific customer testimonials.
“A commuter compared $50k/$100k and $100k/$300k UM/UIM limits and found the higher option added less per month than expected, so they matched their bodily injury limits.”
“A family realized their teen and passengers would be affected by the same policy choices, so they reviewed UM/UIM, collision, and liability limits together before renewal.”
FAQ: Uninsured 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 for your eligible losses.
How much does uninsured motorist coverage cost?
Costs vary by state, driver, insurer, and selected limits. Bankrate reports that adding UM coverage may cost roughly $5 to $25 per month, but your real number should come from a quote using your ZIP code and policy details.
Do I need both UM and UIM?
Many drivers choose both because the risk is not only “no insurance.” It is also “not enough insurance.” Review uninsured-driver rates, state minimum liability limits, your income, savings, and passenger risk before deciding.
Does UM/UIM cover damage to my car?
Not always. UM/UIM bodily injury generally focuses on injuries. Vehicle damage may require uninsured motorist property damage, collision coverage, or another applicable coverage depending on your state and policy.
Can I reject UM/UIM coverage?
In some states, yes, but rejection may need to be in writing. In other states, UM/UIM may be required or structured differently. Ask your insurer what applies in your state.
Should my UM/UIM limits match my liability limits?
Many drivers start by comparing matching limits because it balances the protection they provide to others with protection for themselves. The right choice depends on your budget, state rules, savings, income, and risk tolerance.
Can a UM/UIM claim affect my premium?
It can, depending on state rules, insurer practices, claim history, and the facts of the loss. Ask your insurer how UM/UIM claims are handled at renewal in your state.
Final Takeaways
UM and UIM coverage help protect you from a risk you cannot control: another driver having no insurance or not enough insurance. With uninsured motorists estimated at 15.4% nationally in 2023 and wide state-by-state variation, the coverage can be a useful protection layer for many households.
The best next step is simple: review your declarations page, confirm whether you have UM, UIM, UMPD, or stacked coverage, then quote one or two higher limit options. If the cost difference is small, stronger UM/UIM limits may reduce a major financial blind spot after a serious crash.
References
- National Association of Insurance Commissioners, Uninsured Motorists topic page citing Insurance Research Council 2023 uninsured motorist estimate. Source↩
- Insurance Information Institute, Facts + Statistics: Uninsured Motorists. Source↩
- Insurance Information Institute, Protect Yourself Against Uninsured Motorists. Source↩
- Bankrate, Uninsured Motorist Coverage cost overview. Source↩
- Florida Statutes, Section 627.727, Uninsured and underinsured vehicle coverage. Source↩