The UK taxes visiting athletes relative to overall annual earnings. Even though Bolt receives hundreds of thousands in appearance money, he would lose money if he ran in England.
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But this summer, for the British Athletics London Grand Prix, he can keep all his money. In an unprecedented move, the country's head of Treasury, George Osborne, granted tax amnesty for the event.
London's Grand Prix is an event within The Samsung Diamond League, which is comprised of 14 of the best invitational track and field meetings in the world. Many of the same athletes competed in the 2012 Olympic Games.
It is, of course, not just for Bolt, but it may well lure him back.
"This decision means that London is now a meeting that we can consider for Usain," his agent Ricky Simms told CNBC in an email. "Previously, we didn't consider running in the UK as an option for him."