The riches for the winners of the Championship play-off final will be "better received than ever before" because of the coronavirus pandemic, says sports finance expert Tim Bridge.
According to Deloitte, victory for Brentford would be worth about £160m over three years, while a Fulham win would earn them £135m.
That rises to £265m over five years if they avoided immediate relegation.
The windfall will be a "platform" to aid development on and off the pitch.
The Championship play-off final takes place at Wembley on Tuesday (19:45 BST kick-off).
Brentford would benefit more from victory in what is the most valuable game in world football because they have not been receiving parachute payments, unlike Fulham who were relegated from the Premier League in 2019.
The financial boost of promotion to the top flight this term has added significance in a season heavily impacted by the global Covid-19 pandemic, with the campaign put on hold for more than three months from March.
Broadcast revenues, which make up a large part of the sums estimated by financial analysts Deloitte, ensure Premier League clubs are able to withstand the financial fallout better than clubs in the lower leagues which rely on matchday revenues.
Supporters are unlikely to be allowed back into stadiums to watch matches until October at the earliest, and even then grounds would only be allowed a limited capacity.
"Given the recent impact of Covid-19, it is likely that the financial impact of promotion will be better received than ever before," said Bridge, a director in Deloitte's Sports Business Group.
"Promotion to the Premier League provides clubs with the financial resources to make strategic investments."
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