Every time a trip, business travel, or a long stay abroad comes up, plenty of people worry: “If I just use my phone the way I normally do, am I going to get hit with a shocking bill later?” This article is here to put that worry to rest before you leave.
Here’s the short version: if you use your phone abroad without changing any settings, your data traffic is treated as “international data roaming,” which can lead to surprisingly high charges. The basic way to prevent this is to turn data roaming OFF. From there, if you still want to get online while you’re away, you can pick the connection method that suits you—free Wi-Fi, your carrier’s international roaming package, an eSIM, or a rental Wi-Fi device. Below, we’ll first explain how big bills happen and how to change the settings to avoid them (separately for iPhone and Android), then walk through how to actually get online once roaming is off. (This is general information as of June 2026. Pricing and conditions vary by your plan, device, and destination, so always confirm the latest details with your carrier.)
- How high charges happen in the first place
- How to turn roaming OFF (iPhone / Android)
- Four ways to stay connected after turning it off
- How to get started with an eSIM, and the honest caveats
- What to check when you can’t get connected
Why using your phone abroad as-is leads to high charges
When you take a phone on your home plan abroad and use it as usual, a mechanism called “international data roaming” kicks in, borrowing a local mobile network to keep you connected. This is billed separately from your regular domestic data, and if you don’t have an international roaming package, the charges can pile up based on exactly how much you use.
One thing to watch out for in particular: data gets used even when you’re not actively watching videos. App updates, photo and video cloud sync (such as iCloud or Google Photos), location services in map apps, and automatic syncing of social media and email all keep running in the background even when you’re not looking at the screen. Many of the “I barely touched my phone but the bill was huge” cases come down to this kind of automatic traffic.
Another good thing to know: if roaming is still active, data can start flowing the moment you turn your phone on after landing—or even during a brief layover in a connecting country. That’s exactly why the first step is to make sure data doesn’t get used without your knowledge. Ideally, get the settings below sorted before you leave home so you can travel with peace of mind.
The basic fix: turn data roaming OFF
The most reliable safeguard is to keep data roaming turned OFF. This stops data from being used over local networks and makes it much easier to avoid unintended high charges. The setting is very simple, so take care of it before you arrive (ideally before you even leave home). For an overview of the overall setup process, the setup guide is a helpful companion.
How to turn data roaming OFF on iPhone
- Open the “Settings” app
- Tap “Cellular” (or “Mobile Data”)
- Open “Cellular Data Options” (or “Mobile Data Options”)
- Switch “Data Roaming” to OFF
How to turn data roaming OFF on Android
- Open the “Settings” app
- Go to “Network & internet” → “SIM” or “Mobile network”
- Switch “Roaming” or “Data roaming” to OFF
*The exact names and locations vary a little depending on your device and OS version. If you can’t find it, type “roaming” into the search box within Settings to locate it quickly. After changing the setting, it’s worth a quick glance at the top of your screen to make sure no “Data Roaming” indicator is showing.
For extra peace of mind: “Airplane mode + Wi-Fi”
If you really don’t want any data used without your say-so, there’s another approach: turn airplane mode ON, then turn just Wi-Fi back ON. With this, the cellular network isn’t used at all, and you only get online when you connect to Wi-Fi at a hotel or café. The trade-off is that you’ll have no internet anywhere without Wi-Fi, so if you want to stay connected while you’re out and about, the methods in the next section are a better fit.
Even with roaming OFF, voice calls and SMS (calls and text messages tied to your phone number) work through a separate mechanism, so answering an incoming call or receiving an international SMS may still incur call or messaging charges. If costs are a concern, check the specifics with your carrier’s official information so you know what to expect.
Once roaming is OFF, how do you get online abroad? Four options
Turning roaming off prevents big bills, but on its own it also means no internet when you’re away from Wi-Fi. If you want to “check a map,” “translate or message someone,” or “look at a booking site on the spot,” it’s worth lining up one of the options below. Choose based on your destination, length of stay, and how you’ll use it.
| Method | Best for | Things to note |
|---|---|---|
| Free Wi-Fi only | People who barely use data / short stays | Unusable while out or on the move / mind the security risks |
| Carrier international roaming package | People who want to keep their current number and SMS | Daily rates, eligible countries, and conditions vary by plan (confirm with the carrier) |
| eSIM | People who just want easy data access | Requires a compatible, carrier-unlocked device / generally data-only |
| Rental Wi-Fi device | Groups sharing across multiple devices | You’ll need to pick up/return the device, charge it, and carry it |
There’s no single right answer—what fits depends on “whether you need a phone number or SMS,” “whether you’ll use it on the move,” and “how many people will share it.” If you’re unsure about data amounts or the number of days, the eSIM comparison page lets you search by country, data size, and duration.
The eSIM option: from sign-up to arrival
One connection method that’s been growing in popularity for travel is the eSIM. There’s no physical SIM card to swap—you sign up online before you leave, set it up on your phone, and then simply activate the line once you arrive. You can keep your home SIM (your usual number) in place, leave data roaming OFF, and use only the eSIM’s data. That makes it easy to stay connected while keeping the worry of high charges in check.
The typical flow looks like this:
- Choose a plan that matches your destination, data amount, and number of days
- Buy it online and install the eSIM via QR code or similar (it’s best to do this at home before departure, where you have Wi-Fi)
- Activate the eSIM line after you arrive (activation timing varies by plan, so check the instructions)
To be upfront with you: eSIMs (including Bloomy) are generally data-only. Voice calls and SMS (text messages) tied to a phone number generally can’t be sent or received. That said, app-based calls that use data—such as WhatsApp, Messenger, FaceTime, and similar apps—work as usual as long as you have an internet connection. It helps to think of it this way: the only things you can’t do are “phone-number voice calls” and “SMS.” If you need SMS verification codes (for banking and the like) or must make phone-number calls, consider pairing the eSIM with another method that keeps your current number working (such as a carrier roaming package). For more on how phone numbers and SMS are handled, the phone number & SMS articles are a good reference.
Also, to use an eSIM you need an eSIM-compatible device that is carrier-unlocked. Checking the eSIM-compatible devices page before you go helps you avoid an “it didn’t work” moment after you arrive.
Who an eSIM is—and isn’t—right for
An eSIM isn’t a perfect fit for everyone. It’s worth figuring out whether it suits you before you leave.
- A good fit if you: mainly use data for maps, translation, social media, and browsing / want to keep your current number while easily adding a separate connection for your trip / prefer to avoid swapping SIM cards or picking up and returning a rental device
- Not a great fit if you: want to make voice calls and send SMS from your current phone number abroad / plan to complete processes that require SMS verification on the spot / only have a device that isn’t eSIM-compatible or isn’t carrier-unlocked
If you fall into the “not a great fit” group, don’t force an eSIM-only setup—pairing it with a roaming package or preparing another method will save you trouble.
What to know when choosing an “unlimited” plan
If you watch a lot of video or are staying a while, an unlimited-type plan can be an option too. Keep in mind, though, that even plans labeled “unlimited” may have speeds reduced after a certain amount of use, or may apply a fair use policy (rules that keep things comfortable for all users). Whether tethering (connecting a PC or other device to the internet through your phone) is allowed also varies by plan, and connection speeds change depending on the local network, area, and time-of-day congestion.
Once you understand that “unlimited” doesn’t mean “always fast no matter how much you use,” checking the usage terms before you buy will help you avoid surprises. For a short trip where you can roughly predict your usage, a standard plan with a set data amount can be simpler to understand—and sometimes better value. You can find more on how unlimited plans work and who they suit on the unlimited plan page.
Pre-departure checklist
- Turned data roaming OFF (iPhone / Android)
- Checked how to use airplane mode + Wi-Fi if needed
- Decided on a connection method abroad (roaming package / eSIM / rental Wi-Fi, etc.)
- If using an eSIM, confirmed device compatibility and carrier unlock
- Installed the eSIM while on Wi-Fi before departure
- Prepared a backup method if you need SMS verification or phone-number calls
If you can’t connect or the setup isn’t working
If you’ve set everything up but still can’t get online, don’t panic—check the following. Most issues are resolved by reviewing the settings.
- Whether the eSIM line is selected for data
- Whether data roaming (if your eSIM plan requires it) and line selection are set correctly
- Whether airplane mode is OFF (cellular won’t work while it’s on)
- Whether you’ve arrived and completed line activation
- Whether you’ve restarted the device once to reconnect to the network
If that still doesn’t fix it, the troubleshooting guide walks through steps for different situations. Having clear, step-by-step help to fall back on makes it much easier to stay calm and sort things out while you’re abroad.
What you can do with Bloomy
Bloomy eSIM is designed to be easy to follow even if it’s your first time using an eSIM abroad, with friendly guidance from comparing plans before you buy to setup support afterward. If you want to find a plan by destination, data amount, and number of days, start from the eSIM comparison page; if you want to understand the setup flow, start from the setup guide. If you’d like to learn more about getting your phone ready for travel, take a look at the eSIM guide list as well. Please note that plan pricing, data amounts, and supported countries are subject to change, so confirm the latest details before purchase.
