The 'Kiss You' hitmakers - who are made up of Niall Horan, Harry Styles, Zayn Malik, Louis Tomlinson and Liam Payne - have enlisted the services of Grant Thornton, who look after all the National Lottery big-money winners, to advise them on investment and tax after being recommended the organization by industry bosses.
A source told the Daily Mirror newspaper: "Their success is quite staggering - so are the profits coming with it. The lads had an incredible 2012 and this year looks even bigger.
"Although they're all mature for their age, they are still five young boys at heart, and have all made mistakes - it's part of growing up.
"They've now been assigned a small team at one of the country's top money service providers who will be advising the boys on matters of tax, capital and investment.
"One Direction have become one of Sony's biggest draws and the label wants to make sure the guys are looked after."
Harry, 18, has splashed out on a number of expensive motors including a £100,000 Audi R8 Coupe, a £60,000 Range Rover Sport and a £80,000 classic Porsche since rising to fame in 2010, while Louis, 21, owns a £90,000 Range Rover and forked out £17,000 on a Mini for his girlfriend Eleanor Calder.
Liam, 19, also bought his on/off girlfriend Danielle Peazer a £50,000 Audi TT for her birthday, but he is more interested in splashing his cash on pricey watches such as a £13,000 Hublot and a £3,000 designer Breitling.
While they have a penchant for expensive vehicles, Niall was involved in a car crash on the weekend when the Range Rover he was a passenger in slid off the road and into a crash barrier after skidding on a large patch of ice as he was being driven home from Heathrow Airport. Thankfully, the Irish star escaped uninjured.