The charming prince popped down to his local hall after a hard day of lectures at the nearby Sandhurst military school, the Sun reports.
Locals were gobsmacked when the 24-year-old heir to the throne waltzed in, bought himself a £5 book of bingo cards and played the numbers game for nearly an hour.
Unfortunately for the prince, he did not manage to pick up any bingo prizes, although anyone who was there felt like a winner, playing in such illustrious company.
One player told the paper: "He was very friendly, talking and joking with people at Mecca Bingo.
"When someone asked him to sign the back of their bingo card he borrowed a pen from the girl behind the bar and signed a couple of cards."
According to a source at Sandhurst, William and his friends were contemplating what to do for the evening when one of them suggested bingo, to which William excitedly responded: "That's perfect! Mecca Bingo it is."
If the prince wants to follow his passion for bingo more discreetly in future, he could always play online bingo instead!
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