Indonesia is 17,000 islands, and nearly everyone's trip is Bali plus one or two others. Those are two different coverage situations and two different answers on price.
Bali
Coverage across the south — Kuta, Seminyak, Canggu, Sanur, Ubud — is good. You will not have problems booking a Gojek, loading maps or video-calling home.
Where it thins out:
- The mountain roads around Bedugul and Kintamani: signal comes and goes on the bends.
- North and west Bali (Pemuteran, West Bali National Park): usable in the villages, weak between them.
- Nusa Penida and Nusa Lembongan: coverage in the main areas, patchy at the cliff viewpoints and on the west coast tracks.
- The boat over to the Nusa islands: expect to lose signal mid-crossing.
Java, Lombok, Flores and further east
Coverage follows population, and population drops sharply as you go east.
- Jakarta, Yogyakarta, Surabaya: fine, with the usual congestion slowdowns at peak times.
- Mount Bromo and Ijen: coverage at the viewpoints is unreliable, and the pre-dawn starts are exactly when you want a working map. Download the route the night before.
- Lombok and the Gili islands: good in the main areas; the Rinjani trek has long stretches with nothing.
- Flores, Komodo, Labuan Bajo: towns are covered. On liveaboard boats and around the national park, assume no signal for most of the day.
- Raja Ampat, Sumba, inland Sulawesi and Papua: plan for being offline.
The honest bit about price
A physical SIM bought in Indonesia is often cheaper than a travel eSIM — sometimes noticeably so. We are not going to pretend otherwise.
If you are staying three weeks, you use a lot of data, or you have someone local helping you, buying a local SIM is the sensible choice on money. Be aware that registration requires your passport and takes time at the shop, and that airport counters charge far more than shops in town.
An eSIM is the better trade when:
- Your trip is under two weeks and your time is worth more than the difference.
- You want data the moment you land, for the ride to the hotel.
- You do not want to take your own SIM out and risk losing it.
- You are hopping between Indonesia and other countries in one trip.
How much data
Hotel and café wifi is common in Bali, so most visitors use less than they expect there. Further east, wifi gets slow and your own data carries more of the load.
- Bali, ordinary sightseeing: 2 GB per day is comfortable.
- Posting video and photos daily: 3 GB per day.
- Island-hopping east with poor wifi, or working remotely: 3–5 GB per day, and check hotspot sharing is allowed before you rely on it.
If a plan slows down after its high-speed allowance, it keeps working — just slower. Messaging and maps still function; video is what suffers.
Drivers will try to call you
This is the single most practical consequence of a data-only eSIM in Indonesia. Gojek and Grab drivers routinely ring rather than message when they cannot find you, and you have no Indonesian number to ring.
What works: pin your location precisely in the app, use the in-app chat, and write a landmark into the pickup note. Where a form demands an Indonesian mobile number, your accommodation's number is the usual answer.