The 18-year-old - who participated in The X Factor UK in 2010 with bandmates Zayn Malik, Louis Tomlinson, Liam Payne and Niall Horan - revealed how lucky he felt to perform to audiences in the United States as a British pop act.
He told The Sun: "To come over here and see that so many people know all the songs on an album that isn't even out yet is unbelievable.
"Not many people get to do what we do in England, so for us to come over here and be able to perform to crowds like this is amazing and humbling."
The star even said that their American followers are as enthusiastic as they are in the UK.
He added: "There is one girl who constantly messages us on Twitter. She has been at every hotel we have been to in America so far, trying to lure us on a night out."
Styles recently broke the news that Malik would have to miss some of their US tour due to a tragedy in his family.
He wrote on Twitter: "Zayn has suffered a loss in his family & has had to go home for a few days so won't be at our next shows in the US.
"Our thoughts are with him and his family at this sad time."
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