The mid-tier firm found that 88% of the Premier League clubs expect to make a profit in 2016/17. These clubs will earn TV rights allocations of between £100m and £150m this season.
However, 23% of the Championship and 40% of the Scottish Premiership clubs said their finances need attention or are a case for grave concern.
After interviewing 49 football club finance directors, BDO found 73% of clubs in League Two have received an informal or formal approach from potential equity investors over the last year.
BDO said this suggests investors are more willing to invest in lower leagues where they can see future value growth.
Ian Clayden, head of professional sports at BDO, said the wealth gap between different divisions seems to be widening but, with increasing stability, the financial gap within individual leagues appears to be narrowing.
Clayden said, “With greater emphasis on competition in the field, this promises to be a compelling season in all divisions as English and Scottish football further cements itself as the most exciting, competitive and lucrative in the world.
“With the English Football leagues underway, and the new Premiership season kicking off on Saturday, it will be interesting to see how clubs’ fortunes develop over the coming seasons and how this impacts on investor activity and the quality of the product on offer for fans.”