The findings come following a commission from an unnamed Premier League side, with the study conducted by American sponsorship valuation firm GumGum Sports and London-based digital piracy experts MUSO.
Using the sample of eight matches from the top flight last term, it was found each game attracted an average illegal audience of 7.1 million viewers.
Among the highest of those viewers came from China at one million, but other countries including Vietnam, Kenya, India and Nigeria also featured.
The UK ranked 11th on the list for digital piracy views.
The figure of £1million, that is hitting Premier League clubs every game, comes from the legal and illegal audience and what it would mean for pitch-side advertising and kit sponsorship income.
In a statement, GumGum Sports vice president of partnerships and strategy Jeff Katz said: ‘Clubs and sponsors have never been able to quantify media exposure from unauthorised streaming, which over the years amounts to billions of dollars in unrealised value.
‘Now we have a unique data set that gives an advantage to brand sponsors while also enabling clubs to better demonstrate the value they’re driving on behalf of corporate partners.’
MUSO co-founder and chief executive Andy Chatterley added: ‘Piracy audiences have too long been disregarded as offering no real value to rights holders and distributors, but the reality is that these huge audiences still see the same shirt sponsors and commercials as people watching the game via a licensed channel.
‘Sports rights owners are now waking up to the fact that they are leaving sponsorship money on the table by not measuring, understanding and gaining insight from the piracy audience.’
In the United Kingdom, Sky Sports, BT Sport and now Amazon hold the rights to show Premier League games live over the next three seasons.
With the combined value of their deals worth over £4.4bn, digital piracy is seen as a big threat to the sport that relies heavily on the income from their live TV deals.