hereditary peer

The hereditary peers in the United Kingdom and the Republic of Ireland form part of the peerage in the United Kingdom. As of October 2025, there are 799 hereditary peers: 29 dukes (including five royal dukes, of which the Duke of Edinburgh is a life peerage, the holder being a hereditary earl), 34 marquesses, 189 earls, 108 viscounts, and 439 barons (not counting subsidiary titles). As a result of the Peerage Act 1963, all peers except those in the peerage of Ireland were entitled to sit in the House of Lords. Since the House of Lords Act 1999 came into force only 92 hereditary peers, elected from all hereditary peers, are permitted to do so, unless they are also life peers. Peers are called to the House of Lords with a writ of summons. Not all hereditary titles are titles of the peerage. ...