Wigan Athletic reportedly lost £7m during their battle for Premier League survival last season.
Post-tax losses for 2010-11 came in at £7,155,080, up from just under £4m the previous campaign.
In comparison, fellow Premier League strugglers Blackburn Rovers lost £18.6m and Bolton Wanderers more than £26m.
The Latics continue their battle to stay in the top flight this season against Aston Villa on Saturday.