A loyal toast is a salute given to the sovereign monarch or head of state of the country in which a formal gathering is being given, or by expatriates of that country, whether or not the particular head of state is present. It is usually a matter of protocol at state and military occasions, and a display of patriotic sentiment at civilian events. The toast is usually initiated and recited by the host before being repeated by the assembled guests in unison; the composition varying between regions and types of gathering. There is sometimes a tradition of smashing a glass used for a loyal toast, so that no lesser toast can be made with it.

Throughout the Commonwealth realms, the loyal toast is most commonly composed solely of the words "The Queen" or "The King" (as appropriate), though this may be elaborated with mention of the monarch's position as head of a particular state, such as in Canada, where the Canadian Armed Forces codifies the loyal toast as "Ladies and gentlemen, the King of Canada". If the sovereign holds an honorary position within a Canadian Forces regiment, in that regiment's mess the toast is: "Ladies and gentlemen, the King of Canada, our Captain-General", or whatever rank the monarch may hold. In Australia federally and in some states, the loyal salute is typically "The King and the People of Australia". The phrase "and the People of Australia" was added in the 1990s by governor-general Sir William Deane.

As King Charles III is recognised as the symbolic head of the Commonwealth of Nations, at any event where the guest of honour is a dignitary from any of the fifteen Commonwealth realms, the loyal toast is adapted to be "Ladies and gentlemen, the King, Head of the Commonwealth", and should an honoured guest be from one of the other Commonwealth member-states, the loyal toast is to be recited as "Ladies and gentlemen, the King of Canada, Head of the Commonwealth".

Other unique cases exist in places such as Lancashire, where the salute may be "Ladies and gentlemen, The King, Duke of Lancaster"; in Jersey, where residents will informally say "L'Rouai, nouotre Duc" ("The King, our Duke") in Jèrriais; on the Isle of Man, where "The King, Lord of Mann", is said and at Oriel College, Oxford where members toast to "The King, our Visitor". Similarly, whilst the Loyal Toast is traditionally the first given, it is often the final toast given at official debate dinners at the Oxford Union, following those to the speakers, Committee, and Members.

Members of the Royal Family may neither participate in nor respond to the loyal toast, and the honour may be followed by a playing of "God Save The King", which is either the national or royal anthem of most Commonwealth realms. When ambassadors or similarly senior representatives of other heads of state are present, it has become customary for a toast to be proposed after the loyal toast to "heads of state of other countries here represented". The toast can be adapted for use at some royal foundations. For example, at Christ Church, Oxford, the first toast is always "The King, Visitor of Christ Church".

Official etiquette dictates that the loyal toast may be given following either the introduction of honoured guests and opening remarks, or the completion of all courses of the meal, that it be the first toast given, and that a glass of any beverage other than a cocktail be used. It is also customary not to smoke until the sovereign has been toasted. In carrying out the toast, the event's host will rise and request the audience's attention. Once accomplished and the guests are standing, the host raises his or her glass and recites the toast without any other words or music. The audience then responds to the toast by repeating "The King" or, in Canada, "Le roi", drinking the toast, and seating themselves once more.

In the Royal Navy, however, the toast is given with all attendees seated, a custom practised since King William IV, who had served as a naval officer and experienced the discomfort of banging his head whilst standing suddenly on board a vessel at sea, authorised all in the navy to toast him while sitting down. This practice is also carried out on board the ships of the Royal Canadian Navy, so long as neither the King nor any other member of the Canadian Royal Family is present, in which case the toast is given while sitting only if the royal guest so requests it.

At Christ's College, Cambridge the loyal toast is taken sitting down, which fellows of the college have attributed to the ambivalent attitude of their predecessors to King Charles I. The lawyers of Lincoln's Inn also traditionally take the toast sitting down, a custom dating to the reign of British king Charles II.