Every Scottish league club will be able to access a £50,000 grant to help them through the coronavirus crisis following a donation worth more than £3million.
Edinburgh-based investment manager James Anderson has pledged a £2.5million personal donation which will be topped up by gift aid to be worth £3,125,000.
Some of the money will also be used for two funds to help projects in the clubs' communities.
Anderson was introduced to the Scottish Professional Football League by Hearts owner Ann Budge after donating a significant sum to the club in recent years. But it has been stressed that his new gift is not contingent on the Tynecastle side being saved from relegation.
The only condition for clubs to access grants is that they can prove they provide "support for the wider community in which they are based".
The income could be vital in helping some lower-league clubs play at least some of next season amid extra costs of Covid-19 testing and the loss of gate receipts amid social restrictions.
Anderson, a 60-year-old partner at the Baillie Gifford asset management firm, said: "Football is at the heart of communities across Scotland, and there are not many societal organisations that bring people together nowadays, to catch them in a net when they fall.
"When Covid-19 struck, I realised what a significant loss it would be for towns across the country if their local SPFL club's very survival was threatened.
"This isn't just about the passion on the pitch, which is why we love the game, but about the responsibility our clubs take in communities across Scotland.
"I've seen first-hand over the last few years what a difference clubs can make to people's lives, and so I am very pleased to have been able to offer my support at this difficult time.
"I'm also committing my ongoing support to Scottish football by way of confirming I will make further donations.
"I have also introduced others who share my values and who are committed to do the same. This is the start of our journey, together.
"I have great faith in the SPFL Trust, and confidence that they – and SPFL clubs along with their charitable trusts – will take this opportunity and make a great success of it."
A total of £2.1million will be available to clubs with £400,000 being used to speed up the launch of the SPFL Trust's Scottish Football United fund, a scheme in which the game can "respond to major issues or crisis".
The gift aid portion will set up a new Anderson Fund which will be spent on projects which demonstrate a positive impact on "health, attainment, or inclusion as well as any general related support during the Covid-19 crisis".
Each party has stressed that Hearts played no part in the discussions between Anderson, the SPFL and SPFL Trust, with a statement insisting that the donation comes "without qualification or preconditions relating to future structure or governance at the SPFL".
The statement added: "James Anderson made the request to Ann Budge to be introduced to the SPFL, not the other way around.
"James Anderson has donated millions of pounds to dozens of sport, art, and academic organisations over many years and has a reputation that is beyond reproach.
"It is also worth noting that Mr Anderson has been open to every question asked of him by senior colleagues at the SPFL Trust and the SPFL during this process."
SPFL chief executive Neil Doncaster added: "This extremely generous donation from James will help protect all of our clubs from the very worst effects of Covid-19, enabling them to return to playing as early as it's safe to do so, whilst continuing to reach out and support communities as they have done throughout the pandemic.
"We know the positive power our clubs have within their communities. During this crisis, they have stepped up to support thousands of socially isolated and vulnerable people who desperately needed help.
"On behalf of every one of the SPFL's 42 clubs, I want to sincerely thank James for his timely and extremely generous financial support at this critical moment."
