Category: Reinsurance structures · Reviewed by Simon Temme, Account Executive · Last reviewed 2026-06-05
XL is the standard market abbreviation for excess of loss reinsurance — the principal form of non-proportional reinsurance. The term is used interchangeably with ‘XOL’ and ‘excess of loss’ in slips, treaty wordings and market discussion.
Category: Reinsurance structures Also known as: XOL, excess of loss reinsurance Related concepts: excess of loss reinsurance, non-proportional reinsurance, risk excess of loss, catastrophe excess of loss
The XL abbreviation appears in slip wording such as ‘XL layer 1 of 3’ or in programme structures expressed as ‘Risk XL’, ‘Cat XL’, ‘Per Risk XL’ and ‘Aggregate XL’. Each of these has its own attachment basis, limit structure and pricing conventions. The reader should refer to the underlying entries linked below.
XL is also used to describe individual layer structures within a programme: ‘£25m XL £25m’ is shorthand for ‘£25m of cover in excess of a £25m retention’.
The abbreviation is purely a market shorthand; the underlying legal and regulatory framework is the same as for excess of loss reinsurance. The Market Reform Contract slip typically describes the cover as ‘Excess of Loss Reinsurance’ or ‘XL Reinsurance’ in the type field.
The XL acronym appears throughout reinsurance documentation: programme descriptions, slip placements, treaty statements, reinsurance broker submissions and SFCR (Solvency and Financial Condition Report) disclosure. Industry observers will distinguish between ‘risk XL’ (per-event, individual risk basis), ‘cat XL’ (catastrophic event basis) and ‘agg XL’ (aggregate basis) by reference to the attachment basis in the slip.
An illustrative example: a London market reinsurance submission might describe the programme as ‘Property Cat XL — 3 layers — £175m xs £25m’. This translates to: catastrophe excess of loss reinsurance covering property catastrophes, structured in three layers, providing £175m of cover above a £25m retention.
This entry is part of the Apex Insurance Wiki. Last reviewed by Matt Bartlett on 2026-06-05. Next review: 2026-12-05.
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