Long before he'd mastered a camera, let alone become one of Britain's most successful portrait photographers of stars on both sides of the Atlantic, the seed was sown that Jason Bell would one day move to the Big Apple: "There was a picture of New York on the wall in my childhood home in Camden Town which fascinated me. I remember thinking, 'Wow, that's the capital of the world.'"

So in 2003, with a photography portfolio full of A-listers and several works in the National Portrait Gallery collection, Bell decided to buy an apartment in New York and divide his time equally between there and London. "I had this slight feeling that I'd shot everyone in London and it was time for pastures new. When I arrived in New York I seemed to shed my baggage. I was free to be who I wanted to be. It was thrilling."

Bell soon realised that he was by no means the only Brit getting a kick out of New York. In 2006, on an "Anglomania" shoot of British models and socialites for American Vogue in an English tea room called Tea & Sympathy, the co-owner, Nicky Perry, pointed out to him that there are more than 120,000 British people living in the city. "I suddenly thought, 'Wouldn't it be interesting to find out why all these people left England?' And, of course, I also had all these questions about what I personally was doing there."

The result is a stunning series of photographs, entitled An Englishman in New York, comprising portraits of Bell's fellow settlers in the Big Apple, from celebrities such as Kate Winslet and Sting, to chefs, a helicopter pilot and even a rat-catcher. Flicking through, it's striking how many of the sitters, like Bell, trace their arrival there to a fantasy spun from childhood. It was Ella Fitzgerald's version of Cole Porter's "Manhattan" that hooked the singer Estelle as a teenager, while the artist Cecily Brown describes how, arriving in the East Village, she thought, "I've moved to Sesame Street."

But it is the city's ubiquity in the images peddled by popular culture which made the project such a challenge for Bell. "How do you say 'New York' without creating an image that everyone has seen a million times before? It's the most photographed city in the world." Bell reminded himself to avoid the clichés by asking himself, "What do I remember noticing first when I came here?" He laughs. "Seeing an expensively dressed woman in her 80s on the Upper East Side bending down to pick up dog shit with a perfectly manicured hand."

Despite working closely with his subjects to capture their take on the city, Bell's unexpected location choices did surprise some of the sitters. Rather than shoot historian Simon Schama next to the Doric columns at Columbia University where he teaches, he told him he preferred the subway stop. "I think he was rather tickled," Bell says. Author Vicky Ward was persuaded to sunbathe virtually naked in one of her favourite sun spots, overlooked by skyscrapers and an uninterested crowd – a celebration, Bell says, of the fact that "New Yorkers refuse to be shocked".

In her introduction to the book, the writer Zoë Heller also observes how fitting it is that Bell has photographed so many of his subjects where they work, "because New York is a place of obsessive industriousness", she says. One such picture, which Bell grew to love, depicts lingerie designer Jana Kennedy "in her slightly squalid apartment, making knickers in her bedroom. Frankly, that could've been taken in Manchester," Bell says. "But it captures a very New York story."

So now that an exhibition of some of the portraits is about to open at the National Portrait Gallery in London, has Bell, 41, finally answered the questions he harboured about his own New York story? He answers with a resounding yes. It's been a very emotional journey. One sitter even cried. "Taking part made her realise that in many ways lots of her dreams had come true."

Bell believes that New York has made him a better person, more fulfilled. But perhaps more importantly, he never tires of the view that captivated him as a young boy. "Driving back from the airport, there it is in front of you, like the Emerald City, and you think, 'Wow, I'm coming back to that.'"