Act of Parliament
A law (statute) that has been passed by both Houses of Parliament and received Royal Assent.
Independent editorial summary — not the official statute text. Read the official version on legislation.gov.uk.
An Act of Parliament starts life as a bill introduced in either the House of Commons or the House of Lords. Once the bill has been agreed by both Houses and has been given Royal Assent by the Monarch, it becomes an Act. Acts are described as 'primary legislation' because, unlike statutory instruments and other secondary legislation, they do not depend on any other legislative authority for their validity.
Acts of Parliament sit alongside the common law as the two sources of law in the United Kingdom's uncodified constitution: statute is the law Parliament has deliberately enacted, while the common law developed separately over centuries through the decisions of the courts.
Related terms
Official sources
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