Using an eSIM in Jakarta

What Jakarta is like on a phone

Jakarta is somewhere people come to work rather than to sightsee: meetings, trade fairs, and connections onward to the rest of Indonesia. What shapes daily life is the traffic, which turns short distances into hour-long journeys, so the city runs on app-booked motorbikes and treats time in a vehicle as time to work or watch something. The network along the central business spine carries an enormous number of people well; the kampung lanes behind the towers are another world.

When you land

International flights land at Soekarno–Hatta (CGK), which has several terminals linked by a shuttle train. Switch the eSIM on before immigration, because you may need to open an electronic customs form or arrival document you filled in earlier; these requirements are revised periodically, so check with the Indonesian immigration and customs authorities before every trip. A train runs from the airport into a central station, which at rush hour is incomparably faster than the toll road. Some domestic flights use Halim (HLP) instead.

Where coverage changes

Along the central boulevards lined with office towers the signal is strong, with masts dense enough for the whole city. The metro beneath that spine works on the platform and while the train is moving. What changes is when you turn off the boulevard into a gang, a community lane where houses stand almost wall to wall, and speed falls with how far in you go. On the elevated tollways service is continuous but unsettled, since you are passing mast after mast at speed. Out from the northern harbour toward the Thousand Islands, the line fades once the boat clears the bay and is gone across the water.

What a day here costs in data

Jakarta is heavier on data than the regional average, roughly 1.5 to 2.5GB a day. The main reason is the sheer amount of time spent in vehicles, which people fill with video or calls, on top of several ride bookings and payment scans at nearly every counter. Tether a laptop while stuck on the tollway and you will want more than that. Photography and uploads are minor next to the hours of video.

Districts travellers ask about

• Sudirman–Thamrin — The business spine of towers and metro stations; the strongest coverage in the city, and the one place where taking a call from a hotel lobby actually works.
• Kota Tua — The colonial old town of wide squares and thick masonry; fine out in the square, but inside the museum buildings the walls slow a photo upload noticeably.
• Menteng — Old villa streets under big trees; steadier than the crowded districts, which makes it a sensible base if you work nights on somebody else's time zone.
• Kemang — Cafes and restaurants in the south where many foreigners live; the main road is good, while a place set well back inside a lane is clearly weaker than the lane's mouth.

Day trips out of the city

• The Thousand Islands — Fast boats leave from the northern harbour; the line fades to nothing on the crossing, returns at the islands with villages on them, and stays unpredictable at the small single-resort ones.
• Bogor and the Puncak hills — South into cooler hill country; the tollway keeps service throughout, but the road climbing past the tea estates cuts out in patches on the bends, and it jams badly at weekends.
• Bandung — Reachable by high-speed rail through a series of tunnels, where the line stutters and comes straight back on exit; download whatever you plan to watch before boarding and arrange your onward car in advance.