The singer, who is dating American star Ariana Grande, looked cool and casual in his leather jacket, jeans and Adidas trainers as he arrived at the group's hotel on Tuesday (19 November).
He tweeted on arrival: "Cold afternoon in Dublin!! Good to be back in Ireland though!!"
Bandmate Siva Kaneswaran, meanwhile, looked very dapper in his stylish grey coat and faded jeans. The gorgeous popstar looked happy to be in the Irish capital - probably not surprising considering he was born in the city - and spent time chatting with fans outside the hotel.
"Home!! Ireland!! Excited!!" he tweeted.
Tom Parker and Jay McGuiness were also seen outside the central Dublin hotel although it seems Max George managed to escape this photographer's camera and sneak in unnoticed!
Nathan, Siva and the rest of The Wanted will perform at tomorrow night's Cheerios Childline Concert at Dublin's O2 Arena, hosted by ex-Westlife star Nicky Byrne.
The 16th annual event will also feature performances from Little Mix, Shane Filan, Conor Maynard and Union J, with the aim of raising more than €400,000 for the organisation. All the acts performing and all organisers and the venue have waived their fees so the full profit from the night goes to Childline.
Ahead of that, however, The Wanted will be greeting excited fans at the Dundrum HMV store this morning. A spokesperson for the shop told the Irish Herald security had been beefed up due to the masses of fans expected to descend on the wristband-only event.
"We have extra security arranged and barriers will be erected to control the crowds. We expect hundreds of fans to turn up."
The Wanted will chat with fans and promote their new album Word Of Mouth, which features the fab singles 'Show Me Love (America)' (co-written by Nathan), 'Walks Like Rihanna', 'Chasing The Sun' and more.
Watch The Wanted's music video for 'Show Me Love (America)' below:
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