Components of an Act

This Practice Note is concerned only with the structure of UK legislation passed by, or processed through, the UK’s four legislatures. This falls into two categories—primary legislation, and with one exception, secondary legislation (sometimes called subordinate legislation. The exception is byelaws, whose place in the legislative hierarchy is explained below but not dealt with in detail.

Regnal years

Acts are now cited by reference to years (see below) but before 1963, citations referred to regnal years, ie the year of the sovereign’s reign of the session of Parliament in which the Act was passed.

How to find legislation—principal types of legislation

The principal types of primary and secondary legislation are listed in the table below. In terms of legislative framework and finding the legislation, the chief significance of the type of legislation is that each type uses a different numbering series and form of citation. The different citations are shown in the table.

The type of any piece of primary legislation is apparent from its title. The type of any secondary legislation is stated in the