Liability insurance designed to provide an extra layer of coverage above the primary layer. The excess insurance does not respond, however, until the limits of liability in the primary layer have been exhausted. Because of the method of response, it is often much less costly than the primary layer, per $1,000,000 of coverage. The excess layer provides not only higher limits, but catastrophic protection for very large losses.
a liability coverage form that provides additional insurance above underlying policy limits, but does not necessarily provide broader coverage (compare to UMBRELLA coverage). The excess policy's provisions may match the underlying policies' (often called a "following form"), or it may be narrower, or it may be broader in some ways and narrower in others.