Suing the At-Fault Driver vs. Filing a UIM Claim: What's the Difference?
Once an at-fault driver’s insurance limit runs out, there are technically two paths to recovering the rest — pursuing the driver personally, or turning to your own coverage — and they lead to very different places.
The short answer
Suing an at-fault driver directly means pursuing their personal assets for damages beyond what their insurance paid, which is often difficult to collect on if the driver doesn’t have significant assets. Filing an underinsured motorist claim, by contrast — a process that works much like filing any other insurance claim — means turning to your own policy’s UIM coverage for that same gap, up to whatever limit that coverage carries. In practice, the UIM route is usually the more realistic path to actually recovering money, which is part of why that coverage exists in the first place.
Why a lawsuit against the driver often falls short
A civil judgment against an at-fault driver is only as good as their ability to pay it. Most individual drivers don’t carry substantial assets beyond a home, retirement accounts that are often protected from creditors, and modest savings, none of which necessarily translates into a collectible judgment. Winning a lawsuit establishes that money is owed, but it doesn’t guarantee payment — collecting on a judgment against someone with limited assets can take years, if it happens at all, and often costs more in legal fees than it recovers.
Why a UIM claim is often more practical
Filing against an insurer directly, rather than the driver personally, means dealing with an entity that has the resources to pay and a contractual obligation to do so up to the policy’s limit. That doesn’t mean UIM claims are simple or automatically paid in full — insurers still evaluate the claim, negotiate the amount, and apply their own limits and conditions — but the underlying ability to collect is far more certain than pursuing an individual’s personal assets. This is essentially the reason underinsured motorist coverage exists: it’s designed to be the more realistic backstop when the at-fault driver’s insurance and personal assets both fall short.
The two paths aren’t always mutually exclusive
Depending on the state and the specifics of the case, it’s sometimes possible to pursue both routes — filing a UIM claim for the amount within policy limits while also separately pursuing the at-fault driver for anything beyond that, if there’s a realistic chance of collecting. Some states have rules about the order of these steps, including requirements to notify your own insurer before settling with the at-fault party. Because these procedural rules can affect what’s available afterward, understanding the sequence matters before agreeing to any settlement.
What tends to guide the decision
The choice usually comes down to whether the at-fault driver appears to have meaningful, collectible assets beyond their insurance. If they clearly don’t, spending time and money on a lawsuit against them personally, on top of an available UIM claim, often doesn’t add much. If there’s reason to believe they do have significant assets, pursuing both paths — the UIM claim for the reliable portion and a personal claim for the rest — can make more sense, though it involves more time, cost, and legal complexity either way.
The takeaway
A UIM claim against your own coverage is generally the more collectible path when an at-fault driver’s insurance falls short, because it’s backed by an insurer rather than an individual’s uncertain assets. Suing the driver personally remains an option, but its value depends heavily on whether there’s realistically something to collect.