A notice confirming the style of the title for the 86th Regiment was gazetted by the War Office entry dated 18 May in the London Gazette of 16 – 19 May 1812. It stated:

‘His Royal Highness the Prince Regent, in the
name and on the behalf of His Majesty, has been
pleased to approve of the 86th Regiment being in
future styled, ” The 86th (or the Royal County
Down) Regiment,” and bear the Irish harp and
crown upon the button’.