If you were in central London on Wednesday you might have walked past Prince William without realizing it.

The Duke of Cambridge was spotted in a Big Issue uniform handing out magazines to help the homeless.

Matthew Gardner shared snaps of William on Rochester Row, in Westminster, on social media, writing how his brother-in-law Richard Hannant had seen “a celebrity” so was trying to take a sneaky photo.

William then saw him and crossed the road to chat. The royal even pulled out a card machine after Hannant said he didn’t have any change.

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Hannant, who lives in Bath but works in London, told the BBC: “He was amazing, he was so friendly.

“I think what struck me is we’ve just got past a massive Jubilee event and days later he’s out there supporting a charity like Big Issue.

“I think it’s that that I thought was most amazing because one is a worldwide event, this is just a low-key [event], literally standing on the side of the road with a homeless person.

“I was quite amazed that he could go from one massive event to such a low-key thing.”

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Gardner wrote in his social media caption, “What an honour to have a private moment with our future king who was humble and working quietly in the background, helping the most needy.

“These ‘silent gestures’ often go unrecognized.”

William also posed for a photo with another Big Issue seller and a black cab driver.

The Big Issue is one of the U.K.’s leading social businesses, offering homeless people, or individuals at risk of homelessness, the opportunity to earn a legitimate income, helping them to reintegrate into mainstream society.