Deloitte's Football Money League, based on data for the 2010/11 season, placed Barcelona in second place and Manchester United third. These are followed by Bayern Munich, Arsenal and Chelsea respectively.
Collectively the top 20 clubs earned revenues of €4.4bn – a 3% increase from the estimates published in last year’s report – and nine saw double digit growth in income.
The report says: "The growth and sustained success of domestic leagues is dependent on the size of the market they are able to reach. Success is also dependent on the quality of football on show.
"Whilst clubs in some less well-established football regions are able to sign top players, and pay them well, providing them with a team and quality of football that matches their aspirations will be fundamental to retaining them. For the time being, the biggest European leagues remain the destination for the very best playing talent.
"Robust and transparent governance is fundamental to the quality, integrity and credibility of any competition. If leagues can achieve this alongside competitive balance and maintaining a core of talented domestic players, they will become more attractive to commercial partners and fans at home and abroad. This offers the opportunity to develop a ‘virtuous circle’ where the quality of the league drives increased revenues which can then be re-invested in further improving the league."
For more analysis and the full report, visit Deloitte’s Football Money League page.