The short version
- Both sit on top of general liability, commercial auto, and employers liability (stop-gap in Washington), and pay after those limits are used up.
- Follow-form excess mirrors the underlying policy: same coverage, same exclusions, more limit.
- An umbrella can be broader. It may cover some claims the underlying policies do not, subject to a self-insured retention, and it can drop down to act as primary when an underlying aggregate is exhausted.
- The labels are inconsistent. Some policies called "umbrella" are written as follow-form excess, and some excess policies add their own terms. Read the insuring agreement.
- Large programs stack: an umbrella first, then one or more excess layers above it.
Side by side
| Commercial umbrella | Follow-form excess |
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| Sits above | General liability, auto, employers liability | Usually the same, or another excess layer |
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| Coverage terms | Its own insuring agreement, often following the underlying policies with some broader coverage | Follows the underlying policy's terms |
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| Claims the underlying excludes | May cover some, after a self-insured retention | Not covered |
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| Drop down when underlying aggregate is exhausted | Usually | Sometimes, if the form provides it |
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| Self-insured retention | Applies to claims covered by the umbrella but not the underlying | Not applicable |
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| Its own exclusions | Yes, sometimes narrower than the underlying | Inherits the underlying exclusions, may add a few |
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| Typical place in a program | First layer above primary | Second layer and above, or alone above primary |
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Key terms
| Term | Meaning |
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| Underlying insurance | The primary policies the umbrella or excess sits on, listed on a schedule with required minimum limits |
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| Follow form | The excess policy adopts the underlying policy's terms and exclusions |
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| Drop down | When an underlying aggregate limit is used up, the umbrella pays as if it were primary |
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| Self-insured retention (SIR) | What you pay before the umbrella responds to a claim the underlying policies do not cover |
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| Stacking or tower | Several layers of umbrella and excess written by different insurers to reach a high total limit |
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| Exhaustion | The underlying limit must be paid, often by the underlying insurer, before the next layer responds |
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Which one fits
| Situation | Usually |
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| Small business needing $1 million to $5 million above primary | A commercial umbrella |
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| Contract requires a specific total limit | Umbrella, plus excess layers if needed |
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| You want broader protection, not just more limit | Umbrella, with its terms compared to the underlying |
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| Large fleet or high-hazard operations where umbrella pricing is high | Follow-form excess layers |
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| Excess limits in a specialty line (professional, cyber, D&O) | Follow-form excess written over that specific policy |
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Commercial umbrellas usually do not sit over professional liability, cyber, EPLI, or D&O. Higher limits there come from excess policies written specifically over those lines.
What to check when comparing quotes
- The schedule of underlying insurance and required minimum limits; your actual limits must match. See underlying insurance requirements.
- Whether employers liability is scheduled, which in Washington means stop-gap. See the Washington stop-gap gap.
- Exclusions the umbrella adds beyond the underlying policies.
- Drop-down and SIR terms.
- How defense costs are handled: inside or outside the limit.
- Each layer's attachment point in a stacked program, so there is no gap between layers.
Sources
This page describes coverage commonly found in umbrella and excess policies. Policies differ; what yours covers depends on its wording. Reviewed October 2026.