Buying the 1.2-acre neighbouring site, which is owned by veterans charity Stoll, will reduce the chances of Chelsea having to find a new home.
Chelsea have agreed a deal in principle with Stoll, who will on Wednesday be presented with the findings of a nine-week consultation with residents.
The Stoll board of trustees hope to make a decision in October, which could kick-start Todd Boehly’s plans to redevelop Stamford Bridge and increase its capacity from 42,000 to at least 55,000.
Expansion plans risk angering around 100 local military pensioners whose homes at the Sir Oswald Stoll Mansions site are at risk.
The charity insist that, under current plans, 20 flats would be retained and the huge windfall would be invested in new properties to secure “the best possible outcome for residents.”
Fulham Medical Centre is also based at the site and has warned “over 6500 patients could go without a GP” if the sale of the land goes ahead.
They have launched a “save our surgery” campaign during this consultation period and say “there are currently no plans for a surgery in any future development”.
Chelsea beat 13 rival bids to secure the land, which had been publicly listed for sale by estate agents Knight Frank.
Chelsea co-owner Jonathan Goldstein, a London-based property developer and chief executive officer at real estate company Cain International, is leading the project on behalf of the club.
Architect Janet Marie Smith has been charged with designing what Chelsea believe will be one of the best stadiums in Britain.
It is understood the club has not yet signed off on any future stadium plans. Plans to either demolish and rebuild Stamford Bridge in its current location or relocate to a new site will be presented to supporters before being signed off by the Boehly-Clearlake ownership group.
An option to rebuild the stadium stand-by-stand is increasingly seen as unviable. Rising interest rates and construction costs in the UK present further challenges.
Chelsea Pitch Owners, who own the freehold of Stamford Bridge stadium and the name Chelsea FC, have veto power over any potential move away from the current site in Fulham Broadway and would need 75 per cent of its shareholders to agree to any potential move.
This unique arrangement was put in place by former Chelsea owner Ken Bates, who gifted fans the freehold to the stadium to give them future leverage in certain matters relating to the club.
Any move away from Chelsea’s home since 1905 could prove controversial with supporters, who saw off attempts from previous owner Roman Abramovich to move the club to Battersea Power Station in 2012.
A decision to rebuild Stamford Bridge would leave Chelsea to seek a temporary home, but Twickenham Stadium are reluctant to host them.
Fulham's Craven Cottage and Wembley are potential alternative options.
Chelsea’s plans are subject to planning permission from Hammersmith and Fulham Council, which could take between 12 and 18 months. Construction of a new stadium would then likely take at least another five years but Chelsea hope to move by the end of 2030.