What Is the Largest Building in the US?

"Largest" can mean tallest or greatest floor area. Here are the leaders in each category:

By Height (Architectural Top)

1. One World Trade Center – New York City – 1,776 ft (541 m)
2. Willis Tower – Chicago – 1,451 ft (442 m)
3. Empire State Building – New York City – 1,250 ft (381 m)
4. Bank of America Plaza – Atlanta – 1,023 ft (312 m)
5. U.S. Bank Tower – Los Angeles – 1,018 ft (310 m)

By Floor Area (Total Gross Square Feet)

1. Boeing Everett Factory – Everett, WA – 4,723,727 sq ft (world's largest by volume)
2. The Pentagon – Arlington, VA – 3,702,860 sq ft (world's largest office building)
3. General Motors Renaissance Center – Detroit, MI – 2,832,000 sq ft
4. World Trade Center Oculus – New York City – 2,700,000 sq ft
5. McCormick Place – Chicago, IL – 2,600,000 sq ft (largest convention center)

The Boeing Everett Factory is the largest building by volume (472 million cu ft) and floor area in the US.