Find Out What King Charles Was Called During Rendition of 'Happy Birthday' (Hint: It's Not 'King')

King Charles playfully reacted when the group hit a certain lyric while celebrating his 75th birthday

King Charles' birthday still comes with some royal rules!

The King celebrated his 75th birthday on Tuesday and began the afternoon by launching the Coronation Food Project in Didcot with Queen Camilla. During the visit, King Charles was treated to a rousing birthday serenade with a familiar song.

As seen in a video shared on X by Richard Palmer of the Daily Express, supporters, staff and volunteers joined their voices to sing “Happy Birthday” to the King — although that's not what they called him during the tune.

When the time came to state Charles’ name, the group sang "Happy birthday, Your Majesty," using the correct formal address for the monarch. King Charles raised his eyebrows at the “Your Majesty” mention, in what appeared to be a self-deprecating reaction to his royal role as sovereign.

According to the royal family’s official website, which has yet to be updated in full following the death of Queen Elizabeth in September 2022, "there are no obligatory codes of behaviour when meeting The Queen or a member of the Royal Family." The Royal.UK website outlines that the traditional form is a neck bow from the head for men and a small curtsy for women, though some people prefer to simply shake hands.

Related: Kate Middleton and Prince William Mark King Charles' 75th Birthday with Sweet Family Photos

As for greetings, Royal U.K. states, “On presentation to The Queen, the correct formal address is 'Your Majesty' and subsequently 'Ma'am,' pronounced with a short 'a,' as in 'jam'. "

While King Charles would be referred to as “Sir” on second reference as a male member of the royal family, the “Your Majesty” title can also be used. It would also be appropriate to call Queen Camilla “Your Majesty” because she is the Queen.

Meanwhile, royal family members like Prince William and Kate Middleton should technically be addressed as “Your Royal Highness” and subsequently “Sir” or “Ma’am” from there, the royal family website states.

Related: King Charles Steps Out on His 75th Birthday to Launch New Project Alongside Queen Camilla

Prince William might have a more relaxed attitude around this protocol than previous royal generations, according to one anecdote.

During a visit to the charity Centrepoint with Princess Kate in 2018, fellow lunch guests were given a laminated card with a quick run-down of how to interact with the royal couple. The guidelines included that William and Kate would initiate handshakes and a "respectful lowering of the head" was appropriate over a bow or curtsy.

According to attendee Chelsea Jenkins, Prince William "just laughed" about the card. "He said something about updating it," she said.

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King Charles and Queen Camilla, 76, spent his milestone birthday touring the South Oxfordshire Food and Education Alliance to learn more about how the offshoot of the King Charles III Charitable Fund (which was founded in 1979 as The Prince of Wales’s Charitable Fund and recently rechristened) will “bridge the gap between food waste and food need across all four nations of the United Kingdom, helping people and helping the planet," the palace said.

The King and Queen met staff and volunteers who bring in surplus food and redistribute it to 120 community organizations in need around the counties of Oxfordshire, Berkshire, and Wiltshire. The couple then checked out a packing station, chiller for fresh food, vans loaded for distribution and community kitchen.

Prince William and Princess Kate wished King Charles a happy birthday on social media on Tuesday, and will likely see him later today, as the royals are expected to privately celebrate the King's birthday. Across London, royal tributes included gun salutes and the ringing of the Westminster Abbey bells.

Although Westminster Abbey (where King Charles and Queen Camilla were crowned on May 6) was known for ringing its bells to celebrate the birthdays of numerous senior members of the royal family, the tradition has shifted in recent years.

Before 2020, the bells marked the birthdays of 12 royals. Queen Elizabeth, Prince Philip and their four children — then now-King Charles, Princess Anne, Prince Andrew and Prince Edward— all received the honor, as did Charles' wife, Camilla. Prince William, Kate and their kids — Prince George, 10, Princess Charlotte, 8, and Prince Louis, 5 — completed the list.

However, the bells have only rung for four royal birthdays in 2023: King Charles, Queen Camilla, Prince William and Princess Kate.

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