The Union Flag is flown on Government Department buildings on the following 16 appointed occasions.
The Birthday of The Countess of Wessex
Her Majesty's Accession
The Birthday of the Duke of York
The Birthday of The Earl of Wessex
Commonwealth Day
The Birthday of Her Majesty the Queen
St. George's Day
Europe Day
Coronation Day
The Birthday of The Duke of Edinburgh
The Official Celebration of Her Majesty's birthday
The Birthday of The Duchess of Cornwall
The Birthday of The Princess Royal
Remembrance Sunday
The Birthday of The Prince of Wales
Her Majesty's Wedding Day
The Union Flag is also flown to mark certain other ad hoc occasions including State Visits, State Opening of Parliament and, the deaths of Heads of State. Different guidance is in place for Scotland, Wales and Northern Ireland.