But the royal groom managed to resist temptation and didn't turn around to look at his blushing bride until she had nearly reached the altar. William's best man and brother, Prince Harry, snuck a peek at his soon-to-be sister-in-law Kate as she elegantly glided up the aisle with her proud father Michael Middleton on her arm.
So why didn't William turn to look at his long-term girlfriend and fiancée when she entered the abbey?
WATCH: Princes William and Harry sneak a peek at Kate as she enters quire at Westminster Abbey
The reason is simply because of tradition. While many grooms around the world will turn to watch the emotional moment their bride arrives, customarily in British church weddings, the etiquette is for the groom and his best man to face the altar while the bride makes her journey.
The groom will only turn to his future wife once she has joined him at his side – meaning he really is the last person to see the bride.
In keeping with tradition, William faced the altar while his bride walked up the aisle
William did appear to slightly turn to Kate when she was nearing the end of the aisle and walking halfway up the quire, but he didn't look at her properly until she was at his side.
"You look lovely, you look beautiful," he told his bride. The future King even quipped to his father-in-law Michael: "We're supposed to have just a small family affair."
The Cambridges are celebrating their tenth wedding anniversary next week
In her 2013 biography, Kate: A Biography, royal author Marcia Moody also noted the moment Harry set eyes on Kate. "Harry looked back as Kate started walking down the aisle and reported back to his brother, 'Right, she is here now. Well, she looks beautiful, I can tell you that.'"
The Duke and Duchess of Cambridge are preparing to mark their tenth wedding anniversary on 29 April 2021, although their celebrations will naturally be low-key given the recent death of William's grandfather, the Duke of Edinburgh. The royal family have spent the past two weeks in mourning, while the nation was officially in mourning until 17 April, the day of the funeral.