The sale of the Patek Philippe "Henry Graves Supercomplication", a handcrafted timepiece named after its original owner, a New York banker who ordered it in 1925, was the main event at a jewel and watch auction.
The watch, which weighs more than half a kilogram and comprises 900 separate parts, had been estimated to go for a lower amount, US$15 million.
But frenzied bidding pushed the price up higher, and the final amount paid was "a new world record," Sotheby's said.
The winning bidder, who remained anonymous, will have to fork out a total of $24 million, including the commission.
It took Patek Philippe five years to put the watch together.
Graves's name is right there on the dial.
Tim Bourne, Sotheby's worldwide head of watches, said the sale confirmed the watch's "superstar status".
Bourne called it an "icon of the 20th century, a masterpiece that elevates the discipline of watchmaking to art".
The watch was among 368 timepieces that were up for auction on Tuesday.