The One Direction star, who is set to release his debut solo album later this year, was named joint fifth in the rundown - alongside band-mate Liam Payne who is worth the same amount.
The list of the UK's top ten wealthiest musicians was topped by Adele - who has a £140 million fortune.
Meanwhile, Ed Sheeran’s wealth has risen by more than any other British musician this year after enjoying record-breaking chart success, the Sunday Times Rich List 2018 has revealed.
The Shape of You singer is now the UK’s second wealthiest musician under the age of 30, with his estimated wealth rising by £28m to £80m.
He came in 35th in the overall list, which is topped by Sir Paul McCartney. The former Beatle's £820m worth, shared with trucking heiress wife Nancy Shevell, makes him the richest musician in the history of the Sunday Times Rich List.
Zayn Malik is the only member or ex-member of One Direction not to have increased their wealth in the past year - although he is still worth an eye-watering £35 million.
Harry Styles is up £10 million to £50 million, Niall Horan up £6 million to £46 million, and Liam Payne and Louis Tomlinson are both up £2 million to £42 million.
UK's richest musicians under 30
1. Adele £140m
2. Ed Sheeran £80m
3. Harry Styles - £50m
4. Niall Horan - £46m
5= Liam Payne - £42m
5= Louis Tomlinson - £42m
7. Little Mix - £40m
8. Zayn Malik - £35m
9. Sam Smith - £24m
10. Jessie J - £18m