Twittairport analysed the 618 accounts for September of airports across the globe, which tweet and have accounts.
It claims Heathrow has 171,149 followers a rise of 8.37% up from 166,521.
The study said Gatwick Airport has the second highest number of followers with 84,356, an increase of 4.12% on August.
Other airports making the top ten were Dublin Airport in sixth with 42,707, Dubai Airports ninth with 34,752 and Chopin Airport tenth with 30,691.
Twittairport says airports across the 618 accounts in September had a combined 2,045,018 followers, a rise of 4.29%.