A life peer is a titled noble within the Peerage of the United Kingdom whose honors expire upon their death, rather than descending to an heir. While life peerages existed in limited forms for centuries—often granted to royal mistresses or judges—the modern framework was established by the Life Peerages Act 1958. This act fundamentally altered the composition of the House of Lords by allowing for the appointment of distinguished individuals from various professional backgrounds, regardless of gender, thereby ending the exclusive dominance of hereditary male nobles in the upper chamber.
In the context of heraldry and protocol, a life peer holds the rank of Baron or Baroness for life and is entitled to the style 'The Right Honourable' and the use of a coronet of rank. Though the dignity is not heritable, the children of a life peer are entitled to the same courtesy prefixes—such as 'The Honourable'—as those of hereditary barons. Within the College of Arms, life peers may petition for a grant of arms, or matriculate existing ones, with the specific additions appropriate to their station, including supporters and a peer's helm.