“It was unbelievably fun,” said James.
“I didn’t tell any of my friends, I could [only] tell Bella as she was invited as well.
“I couldn’t even tell my boss, I just took annual leave.”
Speculation has been rife about the finer details of the day, with 1,000 names reportedly on the guest list, which included stars from music, Hollywood and sport.
Fielding questions from listeners, James spoke of how star-studded the event was.
“Every 10 seconds it was a room full of the most famous people in the world,” he recalled.
“I just couldn’t believe. It was like going to Madame Tussauds but the wax was animated and you could interact with the wax and it talked back to you, it was absolutely mad.”
Last year, Swift confirmed on Radio 1 during an interview with James that he would be invited to her wedding.
But there were questions around whether this was going to happen – especially as he was speaking at the Crossed Wires podcast festival in Sheffield the day before.
However, after a few cryptic Instagram stories, James posted on Instagram on Saturday that he did in fact, watch the superstar couple tie the knot.
He has since followed up with a separate Instagram post showing his trip, which included some behind the scenes shots as well as pictures from visiting various tourist destinations.
And there was a lot of preparation that went into getting to New York.
Graham Norton was the only other person in the UK who was publicly invited, so James attended a “secret dinner” at his house so their spouses could meet.
He told listeners on his show that he couldn’t spill all the secrets from the wedding but could share some “fun stuff”.
“I did speak to Taylor and Travis, but on a wedding, you know the bride and groom are very busy, so imagine that but the bride and groom are Travis and Taylor,” he said.
And it sounds like Swift and Kelce opted for some fun details.
While there wasn’t a sit down dinner, the food was “unlimited”.
“There were multiple cakes,” said James.
And what any bride and groom hope for, a party atmosphere.
“There was an open invitation to get up onto the stage and dance while the DJ was on, so I did.”
He joked that the “first 10,000 drinks were free” which led to an “incredible hangover”.
