Liability insurance pays the other people when you cause a crash. Uninsured/underinsured motorist (UM/UIM) coverage is the other direction: it is there when someone else hurts you and cannot pay. The Tennessee Department of Commerce and Insurance (TDCI) Glossary of Insurance Terms puts it in plain language.
| Term | TDCI glossary wording |
|---|---|
| UM/UIM coverage | Pays for the policyholder’s injuries and property damage caused by a hit-and-run driver or a motorist without liability insurance |
| Also pays when | Medical and car repair bills are higher than the other driver’s liability coverage |
| Liability insurance (contrast) | Pays for injuries to the other party and damages to the other vehicle from an accident the policyholder caused |
Source: TDCI Glossary of Insurance Terms.
Two problems, one coverage name
TDCI groups uninsured and underinsured motorist coverage in one glossary entry. Uninsured means the other driver has no liability insurance, or you cannot identify them after a hit-and-run. Underinsured means they have liability insurance, but the medical and car repair bills are higher than that driver’s liability coverage. In both cases, UM/UIM is the coverage on your policy that can respond, subject to its own limits and conditions.
How it differs from liability
TDCI defines liability insurance as coverage that pays for injuries to the other party and damages to the other vehicle resulting from an accident the policyholder caused. Liability protects other people from you. UM/UIM protects you when the other driver’s liability is missing or too small. Tennessee drivers shopping limits should look at both sides of that coin. Background on liability limits: Knoxville Auto Insurance: How to Choose Better Liability Limits, Deductibles, and Protection for Real-World Driving.
What to check on your declarations page
- Confirm UM and UIM limits are listed and that you understand whether they apply per person, per accident, or both.
- Ask whether your policy’s UM/UIM follows your liability limits or uses a different number.
- After a crash with an uninsured or underinsured driver, document the scene and call your insurer promptly. Claim-step overview: related reading on How to File a Home Insurance Claim in Tennessee: A Step-by-Step Guide for 2026 may help you organize questions for your agent.
- Keep collision and comprehensive deductibles in view for vehicle damage that is not a UM/UIM issue: TDCI’s glossary separates collision coverage from comprehensive coverage.
Rate filings do not replace limit choices
TDCI also publishes monthly auto rate tables that show how insurers change prices. A decrease or a zero filing does not change what UM/UIM is for. For filing context, see A 12.7% Tennessee Auto Rate Increase Just Cleared the State Filing System and A 0% Tennessee Auto Filing Still Lets Drivers Move 12.300% — 11,285 Policies Are on That Book.
This article is informational only and does not promise coverage or eligibility. Your policy forms control. If a claim dispute is not resolved with your insurer, TDCI accepts consumer complaints online.
Related reading from All Seasons
- Knoxville Auto Insurance: How to Choose Better Liability Limits, Deductibles, and Protection for Real-World Driving
- TDCI’s glossary separates collision coverage from comprehensive coverage.
- A 0% Tennessee Auto Filing Still Lets Drivers Move 12.300% — 11,285 Policies Are on That Book
- A 12.7% Tennessee Auto Rate Increase Just Cleared the State Filing System
- How to File a Home Insurance Claim in Tennessee: A Step-by-Step Guide for 2026
Free policy review
All Seasons Insurance Group offers a free personal policy review. Call 865-263-1400 or visit asigtn.com/get-a-quote/. This article is informational only and does not promise coverage or eligibility; your policy forms control. Seasons change. So should your coverage.
What is UM/UIM coverage according to TDCI?
TDCI's glossary says uninsured/underinsured motorist coverage pays for the policyholder's injuries and property damage caused by a hit-and-run driver or a motorist without liability insurance, and when medical and car repair bills are higher than the other driver's liability coverage.
How is UM/UIM different from liability insurance?
TDCI says liability insurance pays for injuries to the other party and damages to the other vehicle from an accident you caused. UM/UIM is for when the other driver cannot pay you.
Does UM/UIM cover hit-and-run crashes?
TDCI's definition includes injuries and property damage caused by a hit-and-run driver, subject to your policy terms.
What does underinsured mean here?
In TDCI's wording, UM/UIM also pays when medical and car repair bills are higher than the other driver's liability coverage.
Should my UM/UIM limits match my liability limits?
Ask your agent. TDCI's glossary defines the coverage; it does not set a required limit pairing. Compare both limits on your declarations page.
Does a rate filing change what UM/UIM covers?
No. A rate filing changes price. UM/UIM's role is defined by the policy forms and, for plain-language reference, by TDCI's glossary.
Where can I read the glossary myself?
TDCI publishes its Glossary of Insurance Terms on the Department of Commerce and Insurance website under consumer education.
How can All Seasons help after reading this?
Call 865-263-1400 or visit asigtn.com/get-a-quote/ for a free personal policy review. Informational only; no coverage promises. Seasons change. So should your coverage.
