These are the largest office buildings in North America - the largest of all is the Pentagon with 620,000m2 of floor area, packed into 7 floors. At 490,000m2, the FCA (Fiat Chrysler Automobiles) US LLC HQ and Technology Center is the second-largest, followed by Place du Portage of Canada at 462,636m2, which accommodates around 10,000 office workers. If you are into North America's tallest offices (instead of the largest), check out our list of the tallest office buildings in North America.
Some of the other largest office buildings in North America include:
Complexe Desjardins by Wikimedia/Jeangagnon under CC-BY-SA 3.0 Unported
Image Attribution: https://commons.wikimedia.org/wiki/User:Jeangagnon
Merchandise Mart. Located in Chicago, Illinois, along the Chicago river, the Merchandise Mart is the 9th largest commercial/office building in the world with 372,000m2 of floor space (4 million sq feet), primarily as a retailing and wholesale destination. More..
Merchandise Mart in Chicago by Wikipedia/Daniel Schwen under CC-BY-SA 4.0 ..
Image Attribution: https://commons.wikimedia.org/wiki/User:Dschwen
Apple Park. With a floor area of 260,000m2 spread over 4 floors, the Apple Park can accomodate up to 12,000 employees. It was designed by renowned architect Norman Foster and completed in 2017. More..
Aerial view of Apple Park - by Wikimedia/Daniel L. Lu under CC-BY-SA 4.0 ..
Image Attribution: https://commons.wikimedia.org/wiki/User:Dllu
Brookfield Place. Brookfield Place is the 3rd largest office building in Canada, with a floor area of 276,110.00m2. Brookfield Place is located in Toronto, Canada, and stands at a height of 261.00 meters (856.30 feet), with a total of 53 floors.
Check out the Tallest and Largest Office Buildings