Harry travelled to Italy last Thursday and was originally thought to be spending just 24 hours away from his family, but he was spotted on a British Airways flight on Saturday coming from Fiumicino Airport, reported Hello!
A royal fan even managed to take a sneaky snap of the Prince sitting in the first class section of the plane.
"This morning leaving Rome I got up to use the bathroom and I had to wait. As I'm standing there, I look over and see a guy who looks like Prince Harry. And he has a wedding ring on and looks very tired," the fan posted to Facebook.
"The guy next to him looks like security and is glaring at me. Finally my brain clicks and I realise, it is Prince Harry on the way back to London from Rome. He was at a polo tournament,” they added.
Harry's visit included a game of polo for the Sentebale Polo Cup on Friday afternoon to raise money for his charity Sentebale, which helps children and young people affected by HIV in Lesotho and Botswana.