Elsewhere, Lord Lloyd-Webber is second on the list and U2 third, with their fortunes worth £740 million and £548 million respectively.
Sir Elton John is listed at number four, with £290 million, and rock icon Sir Mick Jagger fifth, with a fortune of £250 million.
Adele, on the other hand, has £125 million, with the London-born star's 122-date global arena tour earning an estimated £138 million at box offices.
The 28-year-old singer has also sold out four shows at Wembley Stadium this summer but has previously admitted she doesn't know if she will tour again, which would severely impact her earning potential in the future.
Speaking to an audience in Auckland, New Zealand, Adele admitted that the reason she has continued to tour is because of her fans.
She shared: "The only reason I've toured is you. I'm not sure if touring is my bag."
But the singer also described her tour - which has seen her perform in front of sold-out crowds across the world - as "the greatest accomplishment in my career".
She added: "It's changed my life. I understand why I do it."