The Peerage of the United Kingdom comprises most peerages created in the United Kingdom of Great Britain and Ireland after the Act of Union in 1801. In that year, the Peerage of Great Britain was replaced by the Peerage of the United Kingdom. The Peerage of Ireland, however, continued until the establishment of the Irish Free State in 1922.
Until House of Lords Act 1999 was passed, all Peers of the UK could sit in the House of Lords. The ranks of the peerage are Duke, Marquess, Earl, Viscount, and Baron.
In the following table of peers, higher or equal titles in the other peerages are listed, as are Life peerages in the Peerage of the UK.