You'll want data the moment the plane doors open — to call a Grab, to load Maps so you know where the driver's taking you, to translate a menu that's all in Indonesian. So the real question isn't whether to get connected, it's convenience versus price: an eSIM that's working before you land, or a physical SIM that's cheaper and gives you a local number.
The quick answer
eSIM or local SIM?
Get an eSIM if your phone supports one and you want data live the second you land — no shop, no queue, no passport paperwork. Get a local Telkomsel SIM if you want the cheapest data, the best coverage out in the villages and on the far coasts, or a local phone number for confirming bookings and rides. Plenty of people I host do both: an eSIM for the airport dash, a local SIM once they've settled in.
eSIM — how it works
An eSIM is just a SIM profile you install over the internet instead of a plastic card you slot in. You buy it before you fly, install it on your home Wi-Fi, and set it to activate when you land. By the time you're off the plane, you have data.
The good:
- No shop, no queue, no handing over your passport at a kiosk.
- You keep your home number active on your physical SIM at the same time, so texts and two-factor codes still reach you.
- You can buy and top up entirely from your phone.
The catches:
- It's pricier per gigabyte than a local SIM.
- You get no local Indonesian phone number — it's data only.
- Your phone has to be eSIM-capable and carrier-unlocked. Most iPhones from the XS on, and recent Pixels and Samsungs, qualify; check your settings for an "Add eSIM" option before you rely on this.
The one I point people to is Airalo — cheap, reliable, and you can set it up in ten minutes on the sofa at home. Holafly is a decent alternative if you want a truly unlimited plan and don't mind paying more for it.
Get an Indonesia eSIM before you flyGet the eSIMExpect roughly USD 5–20 for 5–20GB, depending on the plan and how long it runs.
Local SIM — cheaper, and a local number
If price and coverage matter more than convenience, buy a physical SIM once you're here. Telkomsel has the strongest island-wide signal and by far the best reach in rural areas and on Nusa Penida and Lembongan; XL and Indosat are cheaper and perfectly good in the busy south (Kuta, Seminyak, Canggu, the Bukit).
Since 2018, every Indonesian SIM has to be registered to your passport — so buy it somewhere that will do the registration for you and confirm data is flowing before you walk out.
Tip
Skip the first kiosk you see in the arrivals hall — the airport counters are convenient but marked up, and some sell you far more data than a two-week trip needs. Walk to an official Telkomsel GraPARI store or a proper phone shop in town instead. You'll pay less and the staff will register and test the SIM for you.
A tourist data pack runs roughly IDR 100,000–200,000. You'll get a local number, which is genuinely useful — villa hosts, drivers and restaurants here confirm bookings over WhatsApp and phone calls, and some booking sites won't send an OTP to a foreign number.
What coverage actually looks like
4G is strong and fast across the whole south — Kuta, Seminyak, Canggu, the Bukit where I live — and around Ubud. It gets patchy in the places you'll most want a map:
- The interior of Nusa Penida, away from the main loop road.
- The west and north mountains and the road over to Munduk and the crater lakes.
- Remote waterfalls and the back roads that lead to them.
Note
Before you set off for anywhere rural, open Google Maps and download the offline map for that area. It'll route you even when the signal drops to nothing, which it will somewhere between the main road and the waterfall car park.
eSIM vs local SIM, side by side
| Setup | eSIM: online, before you fly. Local SIM: in a shop after you land, with your passport. |
|---|---|
| Price | eSIM: higher per GB. Local SIM: cheapest data on the island. |
| Local number | eSIM: none, data only. Local SIM: yes — useful for bookings and drivers. |
| Rural coverage | eSIM: rides on a local network, usually Telkomsel. Local Telkomsel SIM: the best you can get. |
| Best for | eSIM: short trips, convenience, keeping your home number live. Local SIM: longer stays, tight budgets, off-the-beaten-track travel. |
Wi-Fi, and the power problem
Most cafés and villas here have decent Wi-Fi, and it's fine for uploading photos or a video call. What it isn't is a substitute for mobile data — the moment you're on a scooter or walking to dinner, you need your own connection to navigate. Treat café Wi-Fi as a bonus, not your plan.
The thing that catches people out isn't signal, it's battery. A day of Maps running, photos, and Grab pins flattens a phone by lunch. Carry a power bank.
Data or calls?
You almost certainly only need data. Between WhatsApp — which everyone here uses for calls and messages — and internet calling, very few travellers ever need traditional voice minutes. A data-only eSIM or a data pack on a local SIM covers just about everything you'll do on a Bali trip.
What about my home number while I'm away?
On an eSIM setup, your physical home SIM stays in the phone, so calls and texts to your home number still arrive — just turn its data roaming off so you're not billed, and use the eSIM for data. On a local physical SIM, you're swapping the card out, so your home number goes quiet unless your phone has two SIM slots or its own eSIM.
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