The Largest Buildings in the World

The world's "largest" building has three different answers, depending on what gets measured. Floor area, meaning total interior space across all stories, picks the New Century Global Center in Chengdu, China at 18.9 million square feet. Footprint, the ground area a building covers, picks Russia's AvtoVAZ Lada car factory at 65 million. Volume, the three-dimensional interior space, picks Boeing's airplane assembly plant in Everett, Washington at 472 million cubic feet. The Burj Khalifa, the world's tallest building, makes none of the top tens for any of those. The list below ranks the largest buildings in the world by floor area, the metric most often used to compare multi-use buildings, airport terminals, malls, and casinos.

1. New Century Global Center (Chengdu, China)

Inside the world's largest building is a beach. A 5,000-square-meter indoor one with actual sand, actual surf, and a 150-meter LED screen running an unbroken loop of sunrises and sunsets over the water. The beach is one of the smaller features. The New Century Global Center, in Chengdu in southwestern China, also holds several hotels, an ice rink, a Mediterranean-themed village, a 14-screen IMAX cinema, a university branch, and shopping levels deep enough that its developer, Chinese conglomerate Entertainment and Travel Group, advertises the building as multiple cities under one roof. Total floor area: 18.9 million square feet, more than three times the Pentagon. The building measures 500 meters long, 400 wide, and 100 tall, took four years to build, and opened in July 2013.

2. Dubai International Airport Terminal 3 (Dubai, UAE)

Most of Dubai International Airport Terminal 3 is underground. A checked bag, after the desk, takes a 56-mile journey through one of the most elaborate baggage handling systems ever built before reaching its aircraft. The complex covers 18.4 million square feet across three connected buildings linked by tunnels, cost a reported $4.5 billion, and exists almost entirely for Emirates. Concourse B opened with the terminal in October 2008. Concourse A opened in January 2013 as the world's first Airbus A380-only concourse. Concourse D opened in 2016 for other international airlines, including Qantas. T3 briefly held the title of largest building in the world by floor area, then lost it to Chengdu in 2013 and has been #2 ever since.

3. Abraj Al-Bait Endowment (Mecca, Saudi Arabia)

The most expensive building ever constructed is in Mecca. Abraj Al-Bait, completed in 2012 at a reported cost of $15 billion, sits immediately next to the Masjid al-Haram and exists to house pilgrims during the annual Hajj. Seven skyscrapers ring the central Makkah Royal Clock Tower, which rises 601 meters and is the fourth-tallest building in the world after the Burj Khalifa, Merdeka 118, and the Shanghai Tower. The clock face on the central tower is the largest four-faced clock anywhere on Earth. Total floor area across the complex: 16.96 million square feet, divided among hotels, prayer halls, a five-story mall, and conference space.

4. Istanbul Airport Main Terminal (Istanbul, Turkey)

Istanbul Airport opened on April 6, 2019 and replaced Atatürk Airport as Turkey's main international hub on day one. Its terminal, designed by Grimshaw Architects with Nordic Office of Architecture, covers 15.5 million square feet under a single roof: the largest single-roof airport terminal in the world. The design capacity once fully phased in is 200 million passengers per year, which would make Istanbul comfortably the busiest airport on the planet. The control tower is shaped like a tulip, Turkey's national flower, and won the 2017 International Architecture Award for the future-project category two years before the runways saw their first aircraft.

5. Iran Mall (Tehran, Iran)

The world's largest shopping mall is in Tehran. Iran Mall, on the city's northwest edge in the Chitgar district, opened in phases between 2017 and 2020 and runs more than 15 million square feet according to Guinness World Records. It was developed by Ayandeh Bank. The complex includes a hotel, a library holding more than 500,000 volumes, a replica traditional Iranian bazaar, a Hall of Mirrors modeled on the Golestan Palace, a convention center, and a sports complex. Roughly the floor area of 200 soccer fields.

6. Frankfurt Airport Terminal 1 (Frankfurt, Germany)

Frankfurt Airport Terminal 1 is the older and larger of the airport's two main passenger terminals, the principal hub for Lufthansa, and a building that has been extended so many times since its 1972 original construction that its current floor area exceeds 14 million square feet across four concourses (A, B, C, and Z). Frankfurt is the fourth-busiest airport in Europe by passenger traffic and the continent's second-largest air cargo hub, behind only Paris Charles de Gaulle.

7. Chongqing East Railway Station (Chongqing, China)

Chongqing East Railway Station opened in 2025 in the Nan'an district of Chongqing, the major metropolis of southwestern China. The building combines high-speed rail, intercity rail, suburban rail, metro, and bus services under one roof, a one-stop interchange of a kind that is structurally common in China and almost unheard of in the West. Floor area: 13.1 million square feet. Peak daily passenger throughput at full capacity: 480,000 people.

8. Aalsmeer Flower Auction (Aalsmeer, Netherlands)

Between 20 and 30 million cut flowers change hands every working day in a warehouse outside Amsterdam. The Aalsmeer Flower Auction (now formally Royal FloraHolland) is the world's largest flower trade and one of the world's largest buildings at approximately 10.7 million square feet of floor space, almost all of it on a single ground floor. The auction operates on the Dutch system: prices start high and tick downward on an electronic clock until a buyer accepts the offered price. Because Aalsmeer is mostly one story, it has one of the largest building footprints in the world but ranks below multi-story complexes by total floor area.

9. Beijing Capital International Airport Terminal 3 (Beijing, China)

Norman Foster designed Beijing Capital International Airport Terminal 3, which opened in March 2008 just in time for that year's Summer Olympics. The roof arches in the shape of a dragon's back and is painted imperial red, Foster's response to a brief that demanded national identity at unprecedented scale. The terminal covers 10.6 million square feet across three connected buildings linked by an internal automated train. In 2018, the last full pre-pandemic year, Beijing Capital handled around 80 million passengers and ranked as the world's third-busiest airport.

10. The Venetian Macao (Macau)

The Venetian Macao is a Las Vegas Sands casino resort on the Cotai Strip in Macau, the world's largest gambling market by revenue. It opened in August 2007 and runs 10.5 million square feet of floor area, 3,000 hotel suites, 350 shops, and operating gondola rides on indoor canals modeled on the originals in Venice. Its sister property next door, originally branded Sands Cotai Central, was reskinned and rebranded as The Londoner Macao in 2021 with a 96-meter Big Ben replica out front and an English-themed interior. The Londoner clocks in at about 9.6 million square feet, which would place it inside the global top 12 on its own.

Largest By Other Measures

Three buildings hold records the floor-area ranking misses. The Surat Diamond Bourse in Gujarat, India opened on December 17, 2023, and at 7.1 million square feet is now Guinness-certified as the world's largest office building, ending the Pentagon's 80-year run as the title-holder. The Bourse is laid out as nine 15-story towers connected by a central spine and houses approximately 4,700 office spaces for diamond traders. Boeing's Everett Factory in Washington state has been Boeing's wide-body assembly site since 1967. The 747, 767, 777, and 787 are all built there under one extraordinarily tall roof. Its floor area is only 4.3 million square feet, but its interior volume of 472 million cubic feet is the largest of any building on Earth. The AvtoVAZ assembly building in Tolyatti, Russia is essentially one enormous shed where Ladas have been built since the 1970s; its 65-million-square-foot footprint is larger than any other building anywhere, though because it has only one floor, its floor area equals its footprint.

Why Not Build Up?

The Burj Khalifa in Dubai is 828 meters tall and contains 3.3 million square feet of floor area, less than a fifth of the largest buildings on this list. Vertical construction is structurally and economically more expensive per square meter than horizontal expansion. The most floor-area-hungry building uses (airport terminals, shopping malls, casinos, factories) all need very large contiguous floor plates that thin towers cannot deliver. Airports add a second constraint: tall buildings near runways are prohibited by aviation safety rules. Shopping centers add a third: tenants prefer ground-floor visibility, which keeps malls low. The result is that the world's biggest buildings by floor area are almost all low- or mid-rise structures with massive ground footprints. The tallest buildings, dramatic as they are, do not really compete with them.

The World's 25 Largest Buildings By Floor Area

Two larger structures sit outside this list as edge cases: the AvtoVAZ assembly building in Tolyatti, Russia (65 million square feet) is a single-story industrial factory, and the New Luosiwan International Trade City in Kunming, China (33.8 million square feet) is a multi-building trade complex rather than a single building.