How To Write A Letter To The Royal Family . Upgrade to quora+ to access this answer access millions more answer s like this browse ad‑free I love talking to other writers, so please feel free to share you experiences/mail. Spa by Diane Huntington Loring Page 3 from spaventura.com If communicating directly with a member of the royal family the letter should begin 'sir/madam' and end 'i have the honour to remain, sir/madam, your royal highness's most humble and obedient servant'. Subject/departement the royal family letter to the royal family send your letter to a member or members of the royal family, using the following address: If you want to send your greetings to the royal family, use the form below or write a letter.