Excess Liability Insurance: When Your Business Needs It

Excess liability insurance adds limits above your primary, or "underlying", liability policies, most often commercial general liability (CGL), business auto liability and employers liability. It pays the part of a covered loss above the underlying limit, and it drops down when paid claims use up an underlying aggregate. Businesses buy it because construction contracts, leases and lawsuits routinely go beyond the $1,000,000 per occurrence limit on a primary CGL policy.

How a quote works matters more than what it is called. Two $5,000,000 "excess" policies can look identical on a certificate, yet one pays defense costs out of its limit while the other pays them on top of it.

What is excess liability insurance?

Excess liability insurance is a second layer of coverage that pays when a covered loss is larger than your primary policy's limit. The underlying policies it sits above, usually your CGL policy, business auto liability and employers liability coverage, are listed on the excess policy's schedule of underlying insurance. When an auto claim settles for $1,800,000 against a $1,000,000 business auto limit, the excess policy pays the $800,000 the business would otherwise owe.

It also does a job buyers often overlook. Your aggregate limit caps what an underlying policy pays for all claims in a policy year, and once claims use it up, the excess policy drops down and responds in its place. Defense costs are where the difference between policies shows up. The ISO umbrella form CU 00 01 pays defense on top of the limit, while many surplus lines excess forms pay only your "ultimate net loss", which includes defense. On those forms, a $1,200,000 legal bill cuts a $5,000,000 layer down to $3,800,000.

Is excess liability the same as umbrella insurance?

Not quite. An umbrella is the broadest kind of excess coverage and the only kind that can drop down and act as primary insurance, over a self-insured retention, for some claims the underlying policies exclude. The other two kinds, follow form and stand-alone excess, only add limits above the coverage below. A warning about follow form: true follow form is rare, so check that each layer's terms match the layer beneath it. For which structure fits which buyer, see our umbrella vs excess liability guide.

When does a business need excess liability coverage?

Most businesses buy excess coverage for one of three reasons: a contract requires it, a landlord or large customer wrote the requirement into a lease or agreement, or the worst realistic loss is larger than $1,000,000. Contracts are the most common trigger. General contractors set minimum total limits, often $5,000,000 or $10,000,000, and want the certificate before you start work.

The third reason needs no contract. US juries returned 1,288 verdicts of $10,000,000 or more between 2013 and 2022, according to the US Chamber Institute for Legal Reform, and the median product liability verdict among them reached $36,000,000.^[1]

Severe losses concentrate in a few places:

• Auto fleets: vehicles on the road are the most common source of verdicts above $1,000,000.
• Work at height or below grade: roofing, scaffold, and excavation work produces catastrophic injury claims.
• Public footfall and products: restaurants, retail, apartments, and anything you make or distribute expose large numbers of strangers.

How do excess liability limits stack?

Excess limits stack in layers, and each layer starts where the one below it ends. A simple small-business tower is a $1,000,000 CGL with a $5,000,000 excess layer above it, for $6,000,000 in total. Large commercial towers often have many layers from several insurers. The excess carrier requires each underlying policy to carry minimum limits, and a typical schedule looks like this:

Keeping those limits is a policy condition. If you cancel or reduce an underlying policy mid-term, the excess policy still pays only as if the required limits were in place, and the gap is yours. Sublimits are the quietest trap: a $250,000 assault and battery sublimit inside a $1,000,000 CGL is picked up by the excess only if it is listed separately on the schedule. At each renewal, have your broker walk through the schedule with you.

How much does excess liability insurance cost?

Excess liability pricing follows the same factors as your primary policies, plus one structural factor: where the layer sits. The first excess million costs the most because it is the layer most likely to pay, and each layer above it costs less per million. Industry class moves the price more than anything else: a roofing contractor or a long-haul trucker pays several times what a consulting firm pays for the same limit. Prices are also rising across the market. Social inflation, claim severity growing faster than economic inflation, added 57 percent to US liability claims over the past decade and ran at 7 percent in 2023, according to the Swiss Re Institute.^[2] Excess layers absorb the top of every large verdict, so they feel the trend first. Our cost calculator shows how your class translates into premium.

This guide is educational in nature and a summary of standard ISO policy language only. The actual terms, conditions and endorsements contained in your policy will control. Consult with a licensed broker about your actual exposures.

Before you bind an excess layer

Excess liability insurance adds limits above your general liability, auto and employers liability policies and pays once the underlying limits are used up. Most buyers need it because a contract or lease requires $5,000,000 or more, though severe verdicts justify the layer on their own. Before you bind, ask for the schedule of underlying insurance and confirm whether defense costs sit inside or outside the limit.