The popular holiday islands of Bali, and particularly neighbouring Lombok, have experienced a series of major earthquakes and aftershocks over the past month.
More than 600 people are understood to have died with hundreds of thousands displaced and thousands tourists requiring evacuation.
Analysis by Forward Keys of the tens of millions of daily flight transactions found travel to Indonesia has been pegged back 26% since that second earthquake.
Prior to the ongoing period of heightened seismic activity on the Pacific Ring of Fire, bookings to Indonesia from January 1 were up 10% on the equivalent period last year.
That growth though ceased after the first earthquake and fell away sharply after the second.
Bali has been particularly badly affected; bookings were up 15.2% on last year but have dipped to 42.9% following the second earthquake.
According to the ITT, travel and tourism accounts for around 10% of total employment in Indonesia, but this is considerably higher in places such as Bali and Lombok.
Olivier Jager, ForwardKeys chief executive, said: “In the face of such an overwhelming natural disaster, it is not surprising that there has been a collapse in travel bookings.
“One can only feel enormous sympathy for Indonesia and for the people of Lombok.”