Follow form excess

~3 min read

Category: Liability programme structure · Reviewed by the Apex broking team · Last reviewed 2026-08-20

In short: A follow form excess policy adopts the terms, conditions and exclusions of the policy beneath it, so that once the underlying limit is exhausted the excess layer pays on the same basis as the primary. Where the excess wording departs from the underlying — through its own exclusions, conditions or definitions — the layers no longer move together, and the difference can leave a claim covered below but uncovered above.

Category: Liability programme structure Also known as: follow form, following form excess, follow-form wording Related concepts: attachment point, excess liability insurance

Definition

An excess layer is described as follow form when its operative wording incorporates the insuring clauses, definitions, conditions and exclusions of a scheduled underlying policy, usually the primary. The intention is that the tower behaves as a single block of cover: whatever the primary would pay, the excess layer pays once the primary limit is used up, differing only in attachment and limit.

True follow form is rarer than the label suggests. Many excess wordings are “follow form subject to” — they incorporate the underlying terms except where the excess policy’s own declarations, conditions or exclusions provide otherwise. Every one of those carve-outs is a place where the layers can part company.

Why deviations create silent gaps

A gap between layers is silent because nobody sees it until a claim is large enough to reach the excess layer. Common sources include:

Additional exclusions in the excess wording — for example a cyber, pollution or insolvency exclusion that the primary does not carry — so a loss that erodes the primary is simply not covered above it.
Different notification provisions. If the excess layer requires notification in its own terms rather than deeming notice to the primary as notice to the layer, a claim notified correctly below can be notified late above.
Exhaustion language. Some wordings require the underlying limit to be exhausted by actual payment by the underlying insurer. A commercial settlement in which the insured or the primary insurer contributes less than the full limit can then fail to trigger the layer at all.
Different definitions of claim, loss or circumstance, which can aggregate claims differently at each level of the tower.

How it works in practice

Excess layers are placed over primary policies in liability towers — public and products liability, professional indemnity, directors’ and officers’ cover — where a single insurer will not, or the buyer prefers not to, carry the whole limit. The broking discipline is wording comparison: reading the excess form against the primary line by line, challenging non-following provisions, and ensuring the schedule correctly identifies the underlying policy it is meant to follow, including at renewal when the primary wording changes and the excess forms are rolled forward unread.

Where a tower is assembled from different insurers, each layer’s wording needs the same check. A tower that follows form on paper but not in substance gives the buyer a limit that exists only for well-behaved claims.

Why it matters

Buyers usually judge an excess layer by price per million of limit. But the layer is only worth buying if it responds when the primary is exhausted, in the same circumstances, on the same basis. A cheap layer with its own exclusions may be no cover at all for the very loss scenarios that made the extra limit worth having. See also the attachment point entry for how and when a layer begins to pay.

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Apex Insurance Brokers serves UK professional services firms and commercial businesses. Call 0117 325 0027, email info@apexinsurancebrokers.co.uk, or request a quotation.

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