American Airlines and United Airlines have agreed to a $95.1m (£71.9m) settlement with the developer of the Twin Towers.
The commercial carriers' agreement to the payout to World Trade Center Properties, owned by developer Larry Silverstein, puts an end to a 13-year litigation.
In total, nearly 3,000 people were killed in the 9/11 terror attacks, which were claimed by al Qaeda and its then leader Osama bin Laden.
Just six weeks before the attacks, Mr Silverstein had signed a 99-year lease for the site, which is jointly owned by New York and New Jersey.
The airlines' insurers are understood to be covering the cost of the payout.
Mr Silverstein has already received a $4.55bn (£3.4bn) payout from his own insurers, six years after the attack.
The latest settlement must now be approved by Alvin Hellerstein, the district judge overseeing the majority of civil litigation stemming from the attacks.
The property developer had initially sought $12.3bn (£9.3bn) from the airlines and airport security companies.
Two years ago, Silverstein Properties won an appeal which found that the judge had underestimated the company's losses due to the attacks.
The final payment would have totalled $97m, but was reduced when two of American and United's insurers become insolvent during the case.
Silverstein Properties said they were "pleased to have finally reached a resolution".
American Airlines, who themselves lost 23 employees and family members, said they would "never forget that terrible day and its lasting impact".
United Airlines declined to comment.
More than 2,750 died when American Airlines Flight 11 and United Airlines Flight 175 crashed into the North and South World Trade Center towers.
A hijacked American Airlines flight crashed into the Pentagon just outside Washington DC, killing 187 people.
A fourth airliner, United 93, was also taken over and believed to be heading for Washington DC, but it crashed into a field in Pennsylvania after the passengers and crew tried to regain control.
Silverstein opened a rebuilt One World Trade Center – the tallest building in New York and the sixth tallest in the world – in November 2014.Let's