It's one of those moments where you stop and appreciate the kindness and honesty of strangers.
And now he is on a quest to find the good samaritan who was honest enough to return the lost property.
Along with the wallet was an unsigned note where the stranger apologises for mistakenly picking up the wallet.
"I am really sorry Tom," said the note. "I picked this up thinking it was my mate's and there was no number. Hope you enjoyed Serbia. Good luck at uni."
Tom is now using the wide-reaching powers of Facebook to track down the stranger and his plea has already been shared more than 17,000 times since posted the message three days ago.
"This is bloody awesome," Tom wrote. "Last weekend, I lost my wallet at Luton airport when I flew back from holiday.
"This morning, I received this in the post at my parents' house (the address on my driving license). There's not a single penny missing – all my cards and ID etc. are all still there! There are some incredible people out there.
"BUT, there's no name or contact details on the note so I can't even say thanks... Share this status for me? LET'S FIND THIS ANONYMOUS LEGEND!"
We have reached out to Tom Watts for further comment.
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