Popsugar Fashion Kate Middleton The Royal Dress Code Rules There Are Very Specific Rules When It Comes to Dressing For the Royal Calendar June 25, 2017 by Marcia Moody View On One Page Photo 20 of 22 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 20 State Opening of Parliament — May/June The Queen: The Imperial State Crown. A floor-length gown worn with her Garter Collar. Prince Philip: His naval uniform. Previous Next Start Slideshow The RoyalsKate MiddletonThe British Royals