Princess Margaret (the Queen’s sister) wore her tiara in the bath.

The good news is that none of this tiara etiquette really exists anymore (except for people who go to state banquets and the like), so feel free to wear tiaras whenever you want.

• Unmarried women shouldn’t wear them- this is why they are often worn on a wedding day.
• Being able to wear a tiara isn’t dictated by your social rank but rather by the occasion (um, and actually being able to afford one or pull strings to borrow one.)
• Tiaras are worn for white tie, occasionally black tie, and state events. This means only very, very fancy times.
• Tiaras are eveningwear. The QUEEN OF ENGLAND did not wear a tiara to Prince William and Kate Middleton’s morning wedding, so neither should you.
• Often for “tiara events” the invitation will state “tiaras will be worn”
• Tiaras shouldn’t be worn in hotels or public ballrooms. Only if your friends are fancy enough to have their own ballrooms. But you can wear them to dinner in a private home if the dress code is white tie- go figure.
• Tiaras should be worn so that the jewels are parallel to the ground or at a slight angle to the ears, never as a “headband”.
• Not etiquette but a fun fact: many royal and other famous tiaras easily break apart into sets of necklaces, earrings, and brooches so the pieces can be worn more frequently. Who knew royals were so thrifty?

Coronets are a different matter and ARE linked to rank and can only be worn by people of that rank. Peers wear a coronet (a silver gilt circlet) along with along with ceremonial robes at the coronation of the Monarch only.