A fire at a nearby electrical substation triggered an unprecedented full-day closure of London Heathrow Airport on March 21, impacting approximately 200,000 travelers. Passengers were left stranded and forced to urgently reorganize travel plans. Heathrow, a major global aviation hub renowned for its extensive international connections, cautioned that “significant disruption” would persist and advised passengers to stay away from the airport until operations resumed.
Amidst these recent events, we examine the world’s top 10 busiest airports, ranked by passenger volume, according to 2023 data from Airports Council International.
Top 10 Busiest Airports Globally
Hartsfield-Jackson Atlanta International Airport
Hartsfield-Jackson Atlanta International Airport, situated in Atlanta, Georgia, consistently holds the position of the world’s busiest airport based on passenger traffic. In recent years, passenger numbers have reached up to 104 million annually.
As of March 2025, Hartsfield-Jackson Atlanta has ascended to become the leading global airport by seat capacity, offering 5.4 million available seats. This figure represents a 3% increase in capacity compared to March 2024, as reported by the travel data platform OAG, which bases its calculations on total airline capacity across both domestic and international flights.
Dubai International Airport
Dubai International Airport ranks second, closely following Atlanta, having processed nearly 87 million passengers.
Dallas Fort Worth International Airport
Dallas Fort Worth International Airport in Texas recorded almost 82 million passengers.
London Heathrow Airport
London Heathrow’s global ranking varies, but it typically handles around 79 million passengers annually.
Following the electrical fire on March 21, a Heathrow representative stated, “As Europe’s busiest airport, Heathrow’s energy consumption is comparable to that of a small city. Consequently, restoring full and safe operations requires considerable time,” as reported by CBS News.
While Heathrow may not currently lead in terms of available seats on scheduled flights, it is recognized by OAG as the world’s most connected airport. This distinction is based on the total number of destinations served and the volume of scheduled connections. Heathrow is consistently acknowledged as Europe’s busiest airport regarding seat availability.
Approximately 12 hours after the operational shutdown, Heathrow issued a statement confirming its reopening. However, travelers were instructed to proceed to the airport only if explicitly advised by their respective airlines, according to CBS News reports.
The updated statement further indicated, “We are now collaborating with airlines to manage the return of passengers who were diverted to alternative European airports. We anticipate resuming full operations tomorrow and will provide further updates shortly.”
Tokyo Haneda Airport
Tokyo Haneda Airport registered slightly under 79 million passengers, approximately 78.7 million.
Denver International Airport
Denver International Airport accommodated around 77.8 million passengers.
Istanbul Airport
Istanbul Airport reported 76 million passengers.
Los Angeles International Airport
Los Angeles International Airport (LAX) processed 75 million passengers.
Chicago O’Hare International Airport
Chicago O’Hare International Airport served 73.9 million passengers.
Indira Gandhi International Airport, Delhi
Indira Gandhi International Airport in Delhi concludes the top ten list with 72.2 million passengers.
Collectively, these ten airports account for 10% of global air traffic volume.