(1) Cover providing excess limits over the normal limits of liability policies and giving additional excess cover for perils not insured by the primary liability policies. (2) In reinsurance cover against an accumulation of losses under one or more classes of insurance arising out of a single event.
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UK: Takes the form of excess of loss reinsurance treaty to protect the reinsured against an accumulation of retained losses arising from one event under different classes of businesses. Example: A storm causing widespread losses affecting property, motor, marine and aviation accounts. Alternative terms: whole account; back-up cover.

To protect accumulations of net loss from a number of classes of business but arising from one event, after the operation of all specific Reinsurances in the separate departments.