Royal Warrants are granted to companies that have regularly supplied goods or services to The Queen, The Duke of Edinburgh, The Queen Mother or The Prince of Wales, advised by the Lord Chamberlain. Each of these members of the Royal family can grant a warrant to any business, but an individual business may hold warrants from more than one Royal and a handful of companies holds all four of them. Strict regulations govern the use of the warrant, which allows the grantee to use the legend 'By Appointment' and display the grantors relevant Royal Arms on their products.

Since the medieval era, suppliers of goods and services to the Sovereign have received formal recognition. Initially this patronage was in the form of royal charters granted to the various guilds, and ultimatly led to the formation of the livery companies. Over the ensuing centuries, this relationship between the Crown and individual companies was formalised by the issue of royal warrants.

A Warrant is initially granted for five years, after which it comes up for review. Warrants may be cancelled at any time, and are automatically reviewed if the grantee leaves the business, or if the firm goes bankrupt or is sold. There are currently approximately 800 Royal Warrant holders, holding over 1100 Royal Warrants, some of which have been held by the same company for over 100 years