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United Kingdom Law


What is an Act?

An Act or Statute is a primary piece of legislation passed by the Parliament. Starting as a Bill, the document is discussed in both Houses of Parliament, where any amendments can be made. The Bill must be passed by both Houses before it can receive Royal Ascent and become an Act.

Statutory Instruments are subordinate or delegated legislation. They are not made through the Parliament, but are made under powers delegated by the Parliament, usually to government ministers. Statutory Instruments usually enact rules, regulations and other matters of details. The power to make secondary legislation will be set out in an Act.

Unlike in many jurisdictions which have written constitutions, the legality of primary legislation in the United Kingdom cannot be challenged in the courts (except for exceptions under the Human Rights Act 1998 and the Scotland Act 1998).

Which version of an Act?

Legislation can be found in several different versions. It is important to know which version you are looking at:

  • As Enacted (or Original) - the legislation as it was originally passed
  • Revised - the legislation with any amendments made by subsequent legislation incorporated into the text
  • Point-in-time - the legislation as it was at a particular moment in time

The UK Parliamentary System

UK Parliament provides information on the current and past business of both Houses of Parliament and their committees. It also has a wealth of general material on the parliamentary system, including factsheets on parliamentary procedure and history. You will also find details of the composition of Parliament and of the government of the day and links to official publications. Bills back to 2001 are also available here.

Find Current Legislation

Current legislation can be found in a number of databases:

Find historical legislation

Ancient laws (pre-1200s)

Several compilations of pre-1200 legislation exist and many can be found through the library catalogue:

Laws from 1235 onwards

Statutes of the Realm is the most authoritative sources for older UK legislation (see Interpretation Act 1978 (UK) s19(1)(b))

Regnal Years

Prior to 1963, Acts of Parliament were numbered using the year of the sovereign’s reign in which the Act was passed, a system known as regnal years. Under the regnal year system, an Act passed early in a parliamentary session has a citation such as 5 Edw. 7, c. 9, for the ninth chapter in the session that commenced in the fifth year of the reign of King Edward 7th. It was common for a session to extend into a second regnal year, giving rise to a citation such as 8 & 9 Geo. 6, c. 4.

For a comparison table see below:

Find repealed legislation


Obsolete and spent acts can be repealed through Statute Law Revision Acts, see below:

Find Parliamentary Papers

The Library has substantial holdings of British Government publications including House of Commons Debates, House of Lords Debates, Parliamentary Papers, and Command Papers.

This material is on the library catalogue, and is mainly located in the 

  • Government Documents Collection and
  • in Special Collections in the Baillieu Library.
  • A extensive guide to parliamentary papers has been written by librarians at the Bodleian Law Library.
  • The House of Commons Information Office has produced a factsheet on Command Papers.

Other databases also include relevant documents:

Find Popular Names for Legislation


Find Bills and Explanatory Notes

A Bill is a draft law; it becomes an Act if it is approved by a majority in the House of Commons and House of Lords, and formally agreed to by the reigning monarch (known as Royal Assent). See this guide to the passage of a bill for more information.

Current bills before the UK Parliament can be found on the UK Parliament website, as well as bills from 2001.

Explanatory Notes are created by the government department responsible for the subject matter of the Act to explain what the Act sets out to achieve and to make the Act accessible to readers who are not legally qualified. Explanatory Notes were introduced in 1999 and accompany all Public Acts except Appropriation, Consolidated Fund, Finance and Consolidation Acts.

Explanatory Notes to current bills can be found on the UK Parliament website, under 'Bill documents' with the relevant bill.

Explanatory Notes to assented legislation can be found on the website, with the relevant act.

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