Former world number one golfer Rory McIlroy is the richest young sportsperson in Britain and Ireland with a net worth of STG110 million ($A198 million) pounds, according to the Sunday Times newspaper's Rich List.
Last year, the 29-year-old signed two 10-year endorsement deals worth $US100 million each, with sportswear brand Nike and club manufacturer TaylorMade.
Tennis player Andy Murray is second in the rankings, with the Scot's wealth estimated at STG83 million ($A149 million) pounds.
A relatively modest STG6 million ($A11 million) pounds increase on the three-times grand slam winner's valuation from 2017 reflects his absence from the court after suffering a hip injury at last year's Wimbledon.
Real Madrid winger Gareth Bale and Manchester City striker Sergio Aguero are in the third and fourth spots respectively.
British heavyweight boxer Anthony Joshua, who most recently earned STG18 million ($A32 million) pounds from his title bout with Joseph Parker, completes the top five.
10 richest young sports stars in the UK aged 30 or under:
1. Rory McIlroy (golf) - STG110 million ($A198 million)
2. Andy Murray (tennis) - STG83 million ($A149 million)
3. Gareth Bale (soccer) - STG74 million ($A133 million)
4. Sergio Aguero (soccer) - STG48 million ($A86 million)
5. Anthony Joshua (boxing) - STG35 million ($A63 million)
6. Eden Hazard (soccer) - STG32 million ($A57 million)
7. Mesut Ozil (soccer) - STG28 million ($A50 million)
8. Theo Walcott (soccer) - STG26 million ($A47 million)
9. Paul Pogba (soccer) - STG25 million ($A45 million)
10. Juan Mata (soccer) - STG24 million ($A43 million)
