Scott Braid, 43, from Kirkcaldy, was due to fly out to Boston on 12 June with his wife and two children.
He applied for his ESTA and once it was approved he thought he was “good to go” and booked the “once-in-a-lifetime trip”.
He told BBC Scotland News: “Out of the blue on Tuesday, I got an email that said there’s been an update on your ESTA status.”
He said it had moved from approved to pending and two hours later it changed to “travel not authorised”.
Scott said he is especially frustrated given that he had a previous ESTA that expired in 2024, and he travelled to America in 2023 with no issues.
“Since I’ve done that ESTA there’s been absolutely no changes to my circumstances,” he said. “That’s the frustrating thing, not knowing why this has happened.”
Scott said he is encouraging his family to go ahead with the trip in the hope he will be able to join them part-way through after securing a visa appointment in Belfast next week.