Short title

The short title is the formal name by which a piece of primary legislation may by law be cited in the United Kingdom and other Westminster-influenced jurisdictions (such as Canada or Australia), as well as the United States and the Philippines. It contrasts with the long title which, while usually being more fully descriptive of the legislation's purpose and effects, is generally too unwieldy for most uses. For example, the short title House of Lords Act 1999 contrasts with the long title An Act to restrict membership of the House of Lords by virtue of a hereditary peerage; to make related provision about disqualifications for voting at elections to, and for membership of, the House of Commons; and for connected purposes.

Unlike the long title, which precedes the preamble and enacting formula, and thus sits outside the main body of text, the short title for modern legislation is explicitly defined by a specific section, typically at the very end or very beginning of the main text. As with the above example, short titles are generally made up of just a few words that describe in broad terms the area of law being changed or the thing affected, followed by the word "Act" and then the year in which the legislation is formally enacted.

A notable exception is Israel, in which this convention is reversed. The short title sits outside the main body of legislation, and the summary description of the law, which is made optional, is defined by a specific section if existing. For example, the Combating Iran's Nuclear Program Act, which under the usual convention would have begun with the long title "An Act to sanction entities assisting Iran in promoting its nuclear program or obtaining weapons of mass destruction or means of carrying weapons of mass destruction and to limit corporations who have business relations with Iran, for its favor or in its territory, as part of the international struggle against Iran's nuclear program" and whose first section would have read "This Act may be Cited As the 'Combating Iran's Nuclear Program Act, 5772-2012'", actually begins with the short title "Combating Iran's Nuclear Program Act, 5772-2012", and its first section reads "The Purpose of this Act is to sanction entities assisting Iran in promoting its nuclear program or obtaining weapons of mass destruction or means of carrying weapons of mass destruction and to limit corporations who have business relations with Iran, for its favor or in its territory, as part of the international struggle against Iran's nuclear program."

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