Oath of allegiance

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25.27Under s 5 of the Parliamentary Oaths Act 1866 any Member of the House of Lords who sits or votes without having taken the oath or affirmed is subject to a penalty of £500. In addition to taking the oath or affirming when first taking their seats, all Members of the Lords must take the oath or affirm:

  1. in every new Parliament;1 and
  2. after a demise of the Crown.

The form of the oath is prescribed by the Promissory Oaths Act 1868, s 2 and the Oaths Act 1978, s 1.2 Members of the Lords who object to being sworn may make a solemn affirmation. Members of the Lords may take the oath or make the affirmation in Welsh or Gaelic in addition to, but not instead of, English.3

The oath is usually taken after prayers, but it may be taken at the end of business before the adjournment (Standing Order No 39(5)).

If any Member of the Lords attends the House or votes without having taken the oath or affirmed, their attendance is not recorded and their vote is invalidated.4


  1. 1. At the beginning of a new Parliament at least two days are usually set aside before the State Opening specifically for Members of the Lords to take the oath (‘swearing-in’ days). New Members of the Lords may be introduced at such sittings, but no other business may be transacted (see para 8.36 ).
  2. 2. See para 8.26.
  3. 3. HL Deb (1982–83) 439, c 224; ibid (2001–02) 626, c 1383.
  4. 4. LJ (1993–94) 418, 422, 682.