If you're reading this, you've already decided to buy data for your trip and are just wondering about the package size: how many GB you'll need for Reunion without running out or overpaying. I'll give you the number quickly and with good reason. And to start, good news that many people don't expect: although Reunion is in the middle of the Indian Ocean, it's a French overseas department and an outermost region of the EU, so your European rate roams here just like on the mainland. The opposite would be unusual. Let's see how many gigabytes to truly buy, not just theorize.
The short answer: your number in one line
For 10 days in Reunion, most people will have more than enough with 3 to 5 GB. A good part of the island's hiking takes place without coverage, so you spend less than you fear. If you work remotely or share with family, it goes up to 10-15 GB. And remember: this is EU data, it roams for free.
That's the picture your search engine and your instinct will cite. Now for the nuance. Reunion is not a destination for "being glued to your phone all day": it's a destination for being glued to the landscape, with your phone tucked away in your backpack while climbing Piton des Neiges or descending into Mafate. This significantly reduces actual consumption compared to a European city where you use data at every cafe. At the same time, there are two uses that do consume a lot: the route and weather apps you consult constantly before each section, and the avalanche of landscape photos and videos you'll want to upload when you get signal back on the coast. The right number comes from balancing these two forces. If you want the general framework of the cluster, you have the hub on how much data you need for travel; here we go into the specific details of Reunion and the gigabytes you'll actually use.
Why Reunion changes the calculation
The reason Reunion isn't calculated like any other destination is simple: half the island has no signal. Mobile coverage is good and stable along the entire coastal strip (Saint-Denis, Saint-Pierre, the west coast of Saint-Gilles and l'Hermitage, Saint-Paul), but it vanishes as soon as you enter the mountainous interior. And the interior is exactly where you'll spend your best days.
The extreme case is the Mafate cirque: it's the only corner of the island with no road access, accessible only on foot or by helicopter, and coverage is practically non-existent. Entire days without data. At Piton de la Fournaise, there's some signal at the enclosure's viewpoints, but it drops as you approach the crater. In the three cirques (Mafate, Cilaos, and Salazie) and on the GR R1 and GR R2 trails, disconnection is the norm, not connection.
What does this mean for your gigabytes? That the hours of maximum "tourist activity" are precisely the hours of zero consumption. You can't spend where there's no network. That's why an intensive hiker in Reunion usually needs less data than an urban weekend tourist. The flip side: when you go down to the coast and regain signal, everything syncs at once (photos, messages, backups), and that's where you need to keep things under control. If you want details on how to connect, I explain it in the internet in Reunion guide.
Reunion is EU, Mauritius is not
This point deserves its own section because it surprises many people and can change your bill. Reunion, despite being thousands of kilometers from Europe, is an outermost region of the European Union and part of the Eurozone. In terms of telephony, this means that "roam like at home" applies: since 2017, a European line works here without roaming charges, just as if you were in Madrid or Marseille. It's not an exotic island outside the rules; for data purposes, it's the EU.
Now, the useful warning. Many people combine Reunion with Mauritius, which is only about 200 km to the northeast and has cheap flight connections. But crossing that small arm of the sea takes you out of the EU: Mauritius is an independent country and is not included in "roam like at home". As soon as your mobile connects to a Mauritian network, you switch to an international rate, which can skyrocket.
If you combine the two islands, don't count on "the same data for everything": what is a European rate in Reunion is international roaming in Mauritius. Plan each leg separately.
The practical rule: for the Reunion leg, your European plan or a dedicated plan is fine, and for Mauritius, you need its own data solution. Don't mix the gigabyte budget for the two, or you'll be in for a surprise. You can see your options for the island in the eSIM for Reunion guide.
How much data apps really use
Before deciding on a package, it's good to know how much each thing you do with your mobile weighs. People tend to overestimate maps and underestimate video. The reality is that video consumes almost everything and the rest are crumbs. These are real figures, rounded so you can do your own math:
| Activity | Approximate Consumption |
|---|---|
| Maps and GPS navigation (online) | 5-15 MB/hour (with downloaded map, almost 0) |
| WhatsApp: chat, audio, and notes | 1-5 MB/hour |
| WhatsApp video call | 200-350 MB/hour |
| Social media (scroll, stories, reels) | 500-900 MB/hour |
| Uploading photos | 2-5 MB per photo (a batch of 30 ≈ 120 MB) |
| Music streaming | 50-150 MB/hour |
| Video streaming at 480p | ~700 MB/hour |
| Video streaming at 1080p | ~3 GB/hour |
| Weather and route apps | a few MB per query |
Notice what this implies for Reunion. Your main uses (checking the route, looking at the weather forecast before climbing, sending an audio message home, uploading a photo from the viewpoint) are all very cheap: we're talking about a few megabytes. What skyrockets the bill is watching series at 1080p at the gîte at night or thoughtlessly uploading 4K videos. If you control video, you control 90% of the expense. You have the complete breakdown by app in the mobile data usage statistics by activity.
How many GB according to your profile and days
This is the table that really matters, the heart of the guide. Find the profile that most resembles yours and cross-reference it with the number of days you'll be staying. These are estimates with a margin: they include maps, messaging, some social media, and uploading photos, with video under control. If you plan to watch a lot of series at maximum quality, move up a tier.
| Traveler Profile | 5 days | 10 days | 15 days | 30 days |
|---|---|---|---|---|
| Map and WhatsApp Tourist | 1-2 GB | 2-3 GB | 3-4 GB | 6-8 GB |
| Photo and Social Media User | 3 GB | 5 GB | 7-8 GB | 15 GB |
| Cirque Hiker (routes + weather + photos) | 2-3 GB | 4-5 GB | 6-7 GB | 12 GB |
| Digital Nomad / Remote Worker | 5-7 GB | 12-15 GB | 18-20 GB | 35-40 GB |
| Family Sharing (2-4 mobiles) | 5 GB | 10 GB | 15 GB | 25-30 GB |
How to read it without getting overwhelmed: if you're the classic traveler who uses Google Maps to get to the trail parking, sends audio messages, and uploads a few photos, you're in the first row and 2-3 GB for ten days will be more than enough. The big jump comes with remote work (video calls, uploading files, cloud backups) and families sharing a single line among several mobiles with kids watching videos. For these two cases, don't skimp: it's worse to run out in the middle of the trip than to have an extra gigabyte. The hiker profile, curiously, falls into the mid-to-low range despite being the most intensive, for the reasons we've already seen: you don't spend data in the mountains because there's no network to spend it on.
The hiker of the cirques uses less data
If your trip to Reunion is primarily trekking (the three cirques, the traverse of Piton des Neiges, the volcano), I have news that will save you money: you will spend considerably less than your head calculates. Intuition says "I'm going to use GPS and the map all day, plus weather apps, plus uploading a photo from the viewpoint every two minutes: that's a lot of gigabytes." Reality says otherwise, because you can't spend where there's no coverage.
Your phone's GPS works via satellite and continues to locate you even if you don't have data; the only thing that needs a network is loading the map the first time. If you have the map downloaded (and in Mafate it's almost mandatory), you navigate for hours with zero consumption. Route apps like Visorando or IGN and weather apps weigh megabytes, not gigabytes, and many cache the forecast. And photos, however many you take, aren't uploaded until you get signal back on the coast: they accumulate and sync all at once.
The actual pattern of a hiker in Reunion is: two, three, four days of almost zero data in the interior, and then a peak when descending to the coastal hotel when everything is uploaded. That's why the hiker profile in the table above is more modest than it seems. Honest advice: if you're torn between 3 and 10 GB for a week in the mountains, stick to 3-5 and only recharge if necessary. I prefer to tell you this, even if we sell larger packages.
Calculate your own consumption before flying
The tables give you a starting point, but the most reliable data is already in your pocket. The most honest way to get it right is to check your own history for the last month in your phone settings and extrapolate it to your travel days. Nobody knows your mobile usage better than your mobile.
How to do it in two minutes:
- On Android: Settings › Network & Internet › SIM/Data usage. You'll see the GB for the cycle and a breakdown by app.
- On iPhone: Settings › Mobile Data, scroll down to the app list (better if you reset the statistics at the beginning of the month for a clean cycle).
Take your monthly consumption, divide it by 30, and you'll have your average daily expenditure. Now adjust it for Reunion with common sense: on vacation, you usually use more social media and the camera, but here you'll spend many hours without coverage inland, which compensates for a lower consumption. If at home you use 4 GB per month (about 130 MB/day) and you're going for 10 days of hiking, the calculation gives you just over 1 GB as a baseline; round it up to 3 GB for the peaks of photo uploads on the coast, and you'll be fine. This method is more valuable than any generic table because it starts from you, not an invented average traveler. And if seeing your numbers scares you, it's almost always due to video: that's where the margin is.
How to stretch your data on the island
With four adjustments made before you leave, a small package can go as far as a large one. The key in Reunion is to prepare your phone for disconnection: have all heavy content downloaded before heading into the mountains and leave only light content for data use. These are the tricks that save the most, from greatest to least impact:
| Trick | What it saves you |
|---|---|
| Offline maps (Google Maps, IGN, route app) | Almost all navigation consumption |
| Lowering video quality to 480p instead of 1080p | From ~3 GB to ~700 MB per hour |
| Backups and photo uploads only over Wi-Fi | Prevents accidentally uploading 1-3 GB at once |
| Disabling autoplay on social media and video | 30-50% of scrolling data usage |
| Activating system Data Saver Mode | A general reduction of 10-30% |
Add two specific habits for this island: download the next morning's stages and weather forecast via hotel Wi-Fi before heading out, and set photo and video backups to "Wi-Fi only," because otherwise, as soon as you get signal on the coast, half your package will be used up syncing your day's gallery. With this, even a remote worker can manage with less than they think. You have the complete list of tricks in the guide on how to save data on your travel eSIM.
If you run out, recharge
I'm going to be direct with a philosophy that saves you money: it's better to run short and recharge than to overbuy. The logic is simple. If you buy a large package "just in case" and it turns out that in Reunion you spend half a week without coverage in the cirques, you pay for gigabytes you'll never use and that often expire with you still on the plane home. On the other hand, if you buy conservatively and run short, the solution takes thirty seconds.
With a digital plan, you don't depend on finding a store or waiting in lines: when you get close to the limit, you add another package from your phone and continue. There's no penalty for recharging, nor are you charged more for doing it twice instead of once. Running short is no longer the drama of old, searching for a phone booth.
My practical recommendation: start with the figure for your profile in the table, deduct a little because on this island you'll be more disconnected than usual, and keep the recharge as a safety net for the peak of uploading photos at the end of the trip. This way, you don't tie up money in phantom gigabytes. The only exception is if you're going to areas where buying on the fly is inconvenient, or if you're a remote worker with meetings you can't miss: in that case, yes, go generous from the start and sleep soundly.
Frequently Asked Questions
How many GB do I need for a week in Reunion?
For 7 days, most people will have more than enough with 2-4 GB. If the trip is mainly hiking, lean towards the lower end because you'll spend hours without coverage; if you work remotely or share a line, account for 8-10 GB for the week.
Does EU roaming work in Reunion?
Yes, fully. Reunion is an outermost region of the EU and a French department, so a European line works here without surcharges, just like on the mainland. Its location in the Indian Ocean changes nothing for European rates.
What if I'm also going to Mauritius on the same trip?
That's where the bill changes. Mauritius is about 200 km away but is an independent country outside the EU, so it's not included in "roam like at home." You'll need a separate data solution for that leg; don't count on the same gigabytes for both islands.
Will I have coverage in the Mafate cirque?
Practically not. Mafate is the only part of the island without roads, accessible on foot or by helicopter, and the signal is almost non-existent. Download maps, routes, and the weather forecast via Wi-Fi before entering, because you won't be able to inside.
How much data does GPS use on trails?
Almost none if you have the map downloaded. GPS locates via satellite without consuming data; it only uses data to load the map for the first time. With offline maps, you can navigate for hours on the trail with near-zero consumption.
Should I run short or overdo it on GB?
Better to run short and recharge. With a digital plan, you can add more gigabytes from your phone in seconds without penalty. Buying too much "just in case" usually turns out worse, especially here, where you'll spend a lot of time without network in the mountains.
Do I need more data for landscape photos?
Less than you think. Photos aren't uploaded until you regain signal on the coast, and an image weighs 2-5 MB. The trick is to set gallery backup to "Wi-Fi only" so everything doesn't sync all at once using data.
Can I share my data with another mobile?
Yes, with the tethering function. It works well on the coast, where coverage is good. Keep in mind that sharing uses as much data as if you were browsing yourself, so if there are several of you, move up a tier in the profile table.
Conclusion
In summary, without fluff: for a typical 10-day trip to Reunion, 3-5 GB is enough for almost everyone, and a good part of the credit goes to the island forcing you to disconnect in the cirques and the volcano. Only go up to 10-15 GB if you work remotely or if several mobiles share the same line. Remember the two key points unique to the destination: your European rate roams for free here because Reunion is part of the EU, but if you jump to Mauritius, you'll switch to international rates. And prepare your phone for the mountains with maps and weather downloaded before you leave.
If I had to give you just one piece of advice: buy tight, carry all heavy data offline, and save your top-up as a safety net. It's cheaper and more convenient than carrying gigabytes you won't use. Once you're clear, get your data plan for the island with the Reunion eSIM and stop worrying: activate it, head up to Mafate, and just enjoy the scenery. And if you're still unsure about how this digital connection thing works, start with what an eSIM is, and you'll understand in five minutes.
