Heathrow passenger levels hit six million in August despite the London hub imposing a cap on airline travellers.
The total was 170% up on the equivalent summer peak month in 2021.
However, the total was down on the 7.7 million passengers who used the airport in pre-pandemic August 2019.
The airport handled 38.4 million passengers between January and August period – four times more than the same eights months last year.
The number of aircraft movements last month rose by 78.5% year-on-year to almost 34,000.
The busiest routes were to Europe and North America, followed by the Middle East and Asia-Pacific.
Heathrow last month extended the capacity cap imposed in July to minimise disruption during the summer peak until October 29.
The airport said the move had resulted in “fewer last-minute cancellations, better punctuality and shorter waits for bags”.
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