Walter Scott and Partners paid its 112 staff a total of more than £40m plus £5m worth of bonuses.
Of that, the company's six directors received £25m - an average of more than £4m.
That was a rise from a total pay bill of £25m in 2014, for 99 directors and staff, plus £6m in bonuses.
During that year, six directors received nearly £14m, plus £3m in bonuses.
Accounts filed at Companies House are not required to state who earns the most, but say "the most highly paid director" received the pay package of more than £8m.
Top roles are occupied by Rodger Nisbet, the executive chairman, and Jane Henderson, the managing director.
Between 2014 and 2015, assets under management at the Charlotte Square office fell from £45.8bn to £42.2bn. These are funds placed in its equity portfolio by institutional investors.
Revenue for the company rose 3% to £208m, and the partnership saw its own assets grow 8% to £239m.
The biggest change in the accounts was in the firm's administrative expenses, down from £124m to £66m.
Much of this is explained by a change to the handling of a disputed tax bill. The firm has paid the bill, on earnings from overseas funds, to avoid further HMRC interest charges. But it does not accept liability for it, and discussions continue.
Walter Scott and Partners was founded in 1983. It was sold by its partners, including its founder Walter Scott, to USA-based Mellon Financial in 2006. The price was reportedly £400m.
Mellon was later taken over by the Bank of New York. Walter Scott has since left and set up another fund management firm.
The US parent company received £100m in dividend payment for 2015, up from £95m for the previous year.
A senior financier at one of Edinburgh's fund management firms was paid £8.2m last year - a rise from £5m in 2014.