The 80-minute flight between Jakarta and Singapore has become the world's fastest growing international route since Indonesia and Singapore inked a deal to expand air links in January.
"The almost 130,000 return seats make Singapore-Jakarta the second largest international route in the world.
No other route in the top 10 has seen growth above 20 per cent," the Centre for Aviation (Capa) noted last week.
It estimates that the number of one-way seats on some 298 flights between the two capital cities will reach 65,000 a week in November, up 24 per cent over the same period last year.
Singapore Airlines operates the most number of daily flights to Jakarta - nine - compared with other SIA destinations.
National carrier Garuda Indonesia has also added a ninth daily flight and is using a bigger plane for at least four of the flights.
This upsizing will see a 46 per cent increase in the number of seats in November, compared with the same period last year.
Tigerair Mandala saw a 14 per cent rise in market share of the route after adding five more daily flights for a total of seven.
The increased air links have put pressure on Jakarta to expand its airport - already running over capacity - to meet demand.