What Is Enhanced Underinsured Motorist Coverage in Maryland?

Enhanced uninsured motorist coverage in Maryland, known in the statute as enhanced underinsured motorist coverage (EUIM), is an auto insurance protection that lets your own policy pay on top of the at-fault driver’s liability insurance instead of being reduced by it. The legal name under Maryland Insurance Code §19-509.1 uses “underinsured,” but the coverage applies to accidents caused by both uninsured and underinsured drivers. Since July 1, 2024, every new private passenger auto policy issued in Maryland includes EUIM automatically unless you sign a written waiver declining it.¹

How the Math Changes With Enhanced Coverage

The difference between standard and enhanced coverage is a question of subtraction versus addition, and it only matters when the at-fault driver’s insurance does not fully cover your damages.

Standard uninsured motorist coverage under §19-509 uses an offset. If you carry $30,000 in UM coverage and the at-fault driver’s insurer pays $15,000, your own insurer owes up to $15,000 more. The $30,000 ceiling is reduced by what the other policy already paid, so $30,000 is the most you ever see.²

Enhanced coverage under §19-509.1 removes the offset. The two policies stack: the at-fault driver’s insurer pays its $15,000, and your insurer can pay up to the full $15,000 of your EUIM limit on top of it. You end up with access to $30,000 total rather than being capped at it.³ On a serious injury claim, that extra layer can be the difference between full recovery and paying medical bills out of pocket.

Once EUIM is on your policy, it replaces standard UM entirely. The separate provisions of §19-509 no longer apply.²

When the Coverage Applies

Maryland treats several situations as “uninsured” for coverage purposes. The obvious case is an at-fault driver carrying no liability insurance at all. A hit-and-run where neither the driver nor the vehicle can be identified also qualifies, and so does a crash where the at-fault driver’s own insurer has denied the claim because the driver violated the terms of their policy.⁴

The “underinsured” side of the coverage is written broadly. Under §19-509.1, an underinsured motor vehicle is any vehicle with liability coverage less than, more than, or equal to your own policy limits. A vehicle with zero insurance qualifies too, since zero is less than any coverage amount. This is a wider net than many states cast, where the at-fault driver has to carry numerically lower limits than yours before you can tap your own coverage.⁵

How You Get the Coverage or Waive It

If you hold a private passenger auto policy issued or bound on or after July 1, 2024, EUIM is already there. You do not add it. You get it by default, and you only lose it by actively declining it in writing.¹

The waiver has specific safeguards under §19-509.1(c):

You must sign a written statement on a form the Insurance Commissioner prescribes. A verbal refusal or silence is not a valid waiver.
Before you sign, your insurer must give you written notice explaining the nature, extent, benefits, and cost of the coverage you would be giving up. If the insurer skips this disclosure, the waiver is not valid.
The waiver form must state, in 14-point boldface type, that refusing to waive means the insurer must provide the coverage, and that the insurer cannot refuse to underwrite you because you want it.

For renewal policies issued before July 1, 2024, the rule works in reverse: the insured had to have affirmatively elected EUIM rather than receiving it by default.¹ If your policy predates the change and you have never discussed EUIM with your insurer, you may not have it.

What EUIM Pays For

EUIM covers damages you are legally entitled to recover from the at-fault driver: medical expenses, lost wages, pain and suffering, and property damage including loss of use of your vehicle. Maryland’s 2020 House Bill 144 clarified that both standard UM and enhanced coverage must include property damage and loss of the insured vehicle, resolving earlier ambiguity.⁶

Your EUIM limits mirror your liability limits unless you choose different amounts, and they cannot exceed your liability coverage. If you carry 100/300/100 liability, that is also the ceiling on your EUIM.⁵ Buying higher liability limits is the only way to buy higher EUIM limits.

One limitation to know about: Maryland does not allow stacking. If you insure three cars on one policy, each with $30,000 in EUIM coverage, you have $30,000 available for a single claim, not $90,000.⁷

Filing an EUIM Claim

You file the claim with your own insurance company, not the at-fault driver’s. People find this disorienting at first. You are making a claim against a policy you paid for, which puts your own insurer on the other side of the table.

For hit-and-run accidents, file a police report as soon as possible. The fact that the other driver is unknown does not block the claim, but a police report is practically a prerequisite for your insurer to process it.⁴

Notify your insurer promptly. Most policies require notice within a reasonable time, and waiting weeks or months gives the insurer grounds to dispute the claim. Document everything from the start: medical bills, repair estimates, and every written communication with your insurer. If the claim becomes contested later, those records are what carry you through.

If your insurer denies the claim or refuses to pay a fair amount, the general statute of limitations for a breach-of-contract lawsuit against the insurer is three years. The underlying personal injury claim also carries a three-year limitations period from the date of injury.

Why It Matters in Maryland

Maryland’s minimum liability requirement is 30/60/15: $30,000 per person for bodily injury, $60,000 per accident, and $15,000 for property damage.⁸ A single emergency room visit after a serious collision can exceed $30,000, and $30,000 is all the at-fault driver’s insurer has to pay per injured person on a minimum policy.

If the other driver carries only the minimum, or carries nothing at all, standard UM coverage with its offset leaves you with a fraction of what you need. Enhanced coverage closes that gap by letting your own limits work on top of whatever the other driver’s policy pays. The additional premium is generally modest relative to the protection, which is a large part of why Maryland now makes EUIM the default rather than an opt-in on new policies.

1
Maryland General Assembly. Maryland Insurance Code 19-509.1
2
Maryland General Assembly. Maryland Insurance Code 19-509
3
Maryland Insurance Administration. Understanding Enhanced Underinsured Motorist Coverage
4
Maryland Insurance Administration. What You Need to Know About Uninsured Motorist Claims
5
Maryland General Assembly. Maryland Insurance Code 19-509.1
6
Maryland General Assembly. Maryland HB0144 – 2020 Regular Session
7
Maryland Insurance Administration. Consumer Advisory – Enhanced Underinsured Automobile Insurance Coverage
8
Maryland Department of Transportation Motor Vehicle Administration. Insurance Requirements for Maryland Vehicles