Regnal years refer to the years in which a king or queen was in power. The first regnal year of a sovereign’s reign begins on the date of accession to the throne, the second year begins on the first anniversary of that date, the third on the second anniversay, etc. For example, King Charles I acceded to the throne on March 27, 1625. The first regnal year of Charles the First therefore, is from March 27, 1625 to March 26, 1626, the second regnal year is from March 27, 1626 to March 26, 1627 and so on.
British statutes enacted before January 1, 1963 are cited by regnal year. The citation includes the title of the act, the regnal year, an abbreviation of the sovereign’s name and the chapter number. Example: An Act for the Further Restraint of Tippling in Inns, Alehouses and Other Victualling-Houses is cited 1 Cha. I, c. 4. This citation references the act as chapter number 4, passed in the first year of the reign of Charles the First.
Regnal years may also appear in other types of historical documents.
There are variations in the way citations appear: a session of parliament may have spanned more than one regnal year, a calendar year may have been added, sometimes the jurisdiction is included and sometimes an abbreviation for the Latin version of the monarch’s name is used.
Black's Law Dictionary contains a list of regnal years. - available in most courthouse libraries
Canadian Guide to Uniform Legal citation, 7th ed. contains the current Canadian practice for citing U.K. legislation. - available in Vancouver and regional courthouse libraries
Dictionary of English Law contains a table of the regnal years. - available in the Vancouver Courthouse Library
How to Cite Legal Authorities contains a list of the regnal years, information on how to cite English acts, and an explanation of dating practices. - available in Vancouver and most regional courthouse libraries
Sweet & Maxwell's Guide to Law Reports and Statutes contains a table of the regnal years and an explanation of the differences between the legal year and the historical year. - available in the Vancouver Courthouse Library
Online Regnal Year Calculator