House of Commons: Hours Sat & Late Sittings

This briefing explores trends in sitting hours of the House of Commons since 1979. It looks at both the length of parliamentary sessions and the number of hours sat and the frequency of late sittings. Data is also included for Westminster Hall, a second chamber which the House of Commons has sat in since 1999. Information is not provided on committees which sit separately from the House.

A session of parliament is a parliamentary ‘year’. It starts with the State Opening of Parliament, where the government’s legislative agenda is presented, and is ended by prorogation. Prorogation brings parliamentary business to an end. Legislation is not carried over unless specific provision is made, but it can be brought again to a new session.

Since 1979 the House of Commons has sat for shorter days, resulting in fewer overall sitting hours per session. This is in part due to major changes to sitting hours, aligning them more closely with normal working hours. This has had a marked effect on the standard parliamentary day: proceedings now begin earlier, and are interrupted (finish) earlier. The number of late sittings (where the House rises after ten o’clock in the evening) has fallen significantly.

Other changes came about as a result of the Fixed-term Parliaments Act 2011, which, coupled with the moving of the State Opening of Parliament to the springtime, led to more consistent session lengths. The Fixed-Term Parliaments Act was repealed in March 2022 with the Dissolution and Calling of Parliament Act 2022.

The overall trend since 1979 has been a general reduction in the sitting hours of the House in each parliamentary session and a shortening of the average length of a sitting day: from 8 hours 55 minutes in 1979-80 to 7 hours 37 minutes in the latest 2021-22 session.

Data for this publication comes from the House of Commons Sessional Returns, available from the Parliament website, which has information dating back to the 1997-98 session. Data for the sessions 1979-80 to 1986-87 came from the House Returns and data for the sessions 1987-88 to 1996-97came from the Sessional Returns, both of which are only available in hard copy.

The data used can be found in our downloadable Excel file above.