Manchester United are the first professional sports team to be valued at more than £2bn according to Forbes Magazine.
A report on Forbes' website on Monday said a recent surge in their share price had boosted the club's value to £2.1bn.
Their shares struggled in early trading on the New York Stock Exchange but have since improved, although they closed 41 cents lower at $16.48 on Wall Street on Monday.
The increase leaves United, English champions a record 19 times, comfortably ahead of the world's second-most valuable sports team, the National Football League's Dallas Cowboys, who are worth £1.34bn.
Forbes put the surge in shares down to brighter earnings prospects from new sponsorship deals and said the demand could continue given the team's potential for lucrative payouts in the Premier League and Champions League.