This was according to the study Twittairport, undertaken by the website solterbeck.net, which assessed the Twitter accounts of airports across the globe.
The study analysed the 646 airports that had accounts in December that tweet and interact on the social networking site.
In December, Heathrow gained 8,397 followers, an increase of 8.25% on November.
The study found Gatwick Airport has the second most followers with 100,735 while Manchester Airport has the third highest with 94,685.
Other airports making the top ten were Los Angeles International Airport in fifth spot with 57,918, while Dubai Airports was eighth with 44,196.
Twittairport says airports across the 646 accounts in December had a combined 2,352,289 followers, up on the 2,254,737 in November, and a rise of 4.38%.