In the United Kingdom of Great Britain and Northern Ireland, the Line of Succession is not chosen by the reigning Monarch, Queen Elizabeth II, but by an act of Parliament which dictates that the heir apparent (or first born now according to the Succession to the Crown Act of 2013) will assume the role of Sovereign upon the death, abdication or retirement of the current Monarch. The Monarch may produce and heir, but the right of that heir to succeed the throne upon their parent’s demise and reign as Sovereign, is secured by Parliament in a hereditary monarchy such as the United Kingdom. In Britain, Parliament controls the succession of the crown and can legislate for anything pertaining to the line of succession under a doctrine known as Parliamentary Supremacy. Any change in the natural order of succession would take an Act of Parliament to secure. Such laws create a balanced and stable transition between one Monarch to another through a system called hereditary monarchy. A hereditary monarchy is one in which the crown is passed down from one member of the royal family to another. It is historically the most common type of monarchy and remains the dominant form in extant monarchies. It has the advantages of continuity of the concentration of power and wealth and predictability of who controls the means of governance and patronage. Provided that the monarch is competent, not oppressive, and maintains an appropriate royal dignity, it might also offer the stabilising factors of popular affection for and loyalty to the royal family. The Heir to the British throne has traditionally, and mostly been a male with the exceptions of Queens Mary I, Elizabeth I, Anne and Elizabeth II, and subsequently titled “The Prince of Wales” since its introduction after the conquest of Wales by King Edward I in 1301. Until the Succession to the Crown Act of 2013 was passed by Parliament, the eldest male issue would become next in line to the throne, skipping over female issue if born first. The Succession to the Crown Act 2013 is an Act of the Parliament of the United Kingdom. It altered the laws of succession to the British throne in accordance with the 2011 Perth Agreement. The act replaced male-preference primogeniture with absolute primogeniture for those born in the line of succession after 28 October 2011, which meant the eldest child regardless of gender would precede his or her siblings.

The current order of succession is outlined below: