Here's a look at the times they've broken protocol and shown a little PDA.
The Duke and Duchess of Cambridge are next in line for the throne after William's father, Prince Charles, and have always maintained a top level of professionalism when they attend royal events, which means they keep their PDA to a minimum.
While the two have made sure to refrain from being overtly affectionate while representing the British monarchy, there have been a handful of times that they've made sweet gestures to one another. When those special and rare moments do happen, they surely put a smile on all our faces. In celebration of their wedding anniversary, here are nine times the Duke and Duchess of Cambridge were captured showing public displays of affection.
1. Wedding Day
The moment the whole world was waiting for! William and Kate's kiss on the balcony of Buckingham Palace was captured by hundreds of cameras and seen by many all over the globe on their wedding day, April 29, 2011.
2. California Kiss
After William's team won a round robin tournament at a charity event in Santa Barbara, California, in 2011, Kate gave her hubby a smooch on the cheek.
3. 2012 Olympics in London
After London won the gold medal in the Men's Team Sprint Track Cycling final, the newlyweds couldn't contain their excitement and lovingly embraced.
4. 20th Commonwealth Games
While attentively watching the swimming competition during the Commonwealth Games in Scotland in 2014, the lovebirds sweetly held hands.
5. Garden Party Love
While chatting with people at the Secretary of State's annual Garden party at Hillsborough Castle in Ireland in 2016, Kate kept close to William by tightly holding onto him.
6. Christmas Hand Holding
As they made their way to the Christmas Day service in 2017, the pair walked hand in hand as they smiled at the crowd.
7. Team Heads Together
After racing each other in a friendly competition at a training day for the Heads Together team for the London Marathon in 2017, William and Kate were all smiles as they cuddled up.
8. Princess Eugenie's Wedding
During William's cousin's Oct. 12 wedding at St. George's Chapel, Kate was captured putting her hand on her husband's thigh. According to body language expert Blanca Cobb the gesture meant a lot. "Even though they're not looking at each other, their body language is saying 'Honey I’m thinking of you,'" she told Elite Daily.
9. Ireland Visit
While posing at the Guinness Storehouse's Gravity Bar in Ireland in March, Kate made a rare public display of affection when she lovingly touched her husband's arm while they shared a laugh.
Relive the couple's wedding day in the video below.