Data roaming: what it is, when to turn it on, and how to avoid extra charges
With a travel eSIM, roaming stays on for the travel line and off for your home line, which reverses the usual advice.
One switch in your phone’s settings decides whether you can load a map abroad, and whether your next bill carries a surprise. This page explains what that switch does, how charges reach you, and how to set it when there are two lines on the phone.
What data roaming means: using data on another carrier’s network
Data roaming is the setting that lets your phone use mobile data on another carrier’s network when you are outside of your mobile carrier’s coverage, usually abroad. With it on, data works and your home carrier may bill roaming charges. With it off you rely on Wi-Fi, though a travel eSIM line needs it on.
Apple’s own wording is that Data Roaming permits internet access over a cellular data network when you are in a region your carrier’s network does not cover. Google describes the Pixel’s Roaming setting the same way, as letting your phone send data over other carriers’ networks once you leave your carrier’s coverage area. Samsung labels the Galaxy switch Data Roaming Access.
The switch governs mobile data only. AT&T notes that with data roaming off you can still make calls and send texts but cannot use mobile data. Wi-Fi keeps working whatever the setting says.
Whether it should be on depends on the line it belongs to. On a home plan with no international allowance, off is the safe default abroad. On a travel eSIM it normally has to be on, and eSIMply’s own installation guide ends with the step to turn Mobile data and Roaming ON once you arrive.
How data roaming works, and where roaming charges come from
Roaming is an arrangement between carriers that your phone opts into with one setting. What it costs is set by your home carrier’s plan, and the bill for roaming comes from them.
What happens when data roaming is on
No carrier covers the whole world, so home carriers sign roaming agreements with operators in other countries. According to the GSMA’s explainer on how roaming works, your mobile phone picks up the radio signal from a local operator’s cell sites when you switch it on abroad, and that operator checks with your home network that you are a valid customer allowed to roam. Once the check passes, you can use data services on the partner network.
With data roaming on, every app uses data the way it does at home, including the traffic you never see. Verizon names app refreshes, email syncing and software updates as background data that can start a paid TravelPass session once cellular data or data roaming is turned on.
With data roaming off, your phone connects to Wi-Fi as normal but will not open a data session on another carrier’s network. Apple’s roaming options article treats that as the first thing to check when a line abroad shows No Service or SOS only.
Roaming plan, daily pass or pay-per-use: how charges reach your bill
The foreign operator records what you use and sends those records, with its charges, to your home carrier. Your home carrier adds them to your next bill in your own currency, and the GSMA notes the handover can take some time, so roaming charges can surface after you are home. The GSMA also points out that when roaming you pay for calls you receive as well as calls you make.
What you pay is set by your home plan, and carriers charge in one of three ways: an allowance already included, a daily pass or roaming plan, or pay-per-use rates. Many providers offer international roaming plans you can buy ahead of time, and Apple says carriers might include international roaming on select data plans without additional fees, so check yours before assuming the worst.
Daily passes are the common US model. AT&T International Day Pass costs $12 a day on land for one line, $6 for each extra line used the same day, and $20 a day at sea, with no more than 10 land daily fees per line per bill period. Verizon TravelPass is $12 per line per day, or $6 in Canada and Mexico.
Pay-per-use is where roaming fees get out of hand. AT&T’s pay-per-use data rate is $2.05 per MB, which puts a single gigabyte at more than $2,000.
Domestic roaming vs international roaming
Roaming can happen inside your own country too, whenever you go outside your normal coverage area. Google defines the Pixel setting by leaving your carrier’s coverage area, wherever that is, and Samsung notes that most carriers work together so you can connect to other networks, even outside of the United States.
Roaming typically costs extra when it is international, since partner networks abroad fall outside a domestic allowance unless your plan includes them. If you switch data roaming off at home and lose data in a remote area, a partner network is the likely reason.
Data roaming inside the EU
If your plan comes from a European Union country, Roam Like At Home applies automatically in all 27 EU countries plus Iceland, Liechtenstein, Norway, Ukraine and Moldova. Calls, texts and data are charged as at home, though on unlimited or very cheap plans your operator can set a fair-use data limit and must warn you before you reach it. The European Commission says operators should also tell you when you have used 50 euros and again at 100 euros in a monthly billing period.
The scheme assumes you travel and come home. Your Europe explains that if over four months you spend more time abroad and roam more than you use your phone at home, your operator can ask you to explain and then add capped surcharges. Since the UK left the EU, UK government guidance says surcharge-free roaming in EU and EEA countries is no longer guaranteed for UK customers.
Data roaming with a travel eSIM: on for one line, off for the other
A phone carrying a travel eSIM has two lines, each with its own Data Roaming switch, and they need opposite settings. The usual advice to switch roaming off applies to only one of them.
When to turn on data roaming: your travel eSIM line
A travel eSIM connects you through a network in the country you are visiting, which is why its setup instructions include roaming. eSIMply’s installation guide finishes with the arrival step, turn Mobile data and Roaming to ON, and every eSIMply product page says to activate by enabling the eSIM and data roaming.
Apple gives the matching fix. When a line abroad shows No Service or SOS only, tap that number, open Cellular Data Options and make sure Data Roaming is on. Follow the generic advice to switch roaming off before you fly, and you can end up disabling the line you bought for the trip.
When to turn off data roaming: your home line
Keeping your home line switched on keeps your number reachable, and it is also the line your carrier bills for roaming. Apple’s travel eSIM guidance says that with both lines on, your travel eSIM will be used for data, and you might still incur roaming fees from your home eSIM.
Daily passes can turn that into a fixed daily fee. AT&T says that if you forget to sign up, it will add International Day Pass to smartphones when you arrive in an included destination, and Verizon starts a 24-hour session when you make or answer a call, send a text or use data. On a Verizon line with TravelPass, one answered call can cost a full day’s fee.
Why data switching should stay off abroad
iPhone and Pixel both have a setting that lets the phone borrow data from the second line. Apple’s Dual SIM guide describes Allow Cellular Data Switching as using either line depending on coverage and availability, and in the same passage warns that you may incur roaming charges if Data Roaming is on outside your carrier’s network. On Pixel the equivalent is Automatic data switching, under Network & internet and then SIMs.
Abroad, that second line is your home plan at roaming rates. Keep data switching off, and keep the home line’s data roaming off as a second lock.
Four ways to set up your phone for a trip
- Travel eSIM only. Turn the home line off and let the travel eSIM carry everything. Apple notes that FaceTime and iMessage keep working on your home telephone number this way.
- Travel eSIM for data, home number for calls and texts. Data roaming on for the eSIM, off for the home line, with the eSIM chosen as your data line. eSIMply’s help article on data-only eSIMs warns that your home provider may still charge roaming for calls and texts.
- Home plan only. If roaming is included or you bought a pass, data roaming has to be on for the home line. Verizon says you must turn on cellular data or data roaming to use TravelPass.
- Local SIM card. Swapping in a physical SIM card from the country you are visiting also avoids roaming on your home plan. AT&T points out that your home number stops working until you switch back, and Apple reminds you to keep the original SIM card safe for the trip home.
How to turn data roaming on or off on iPhone, Pixel and Galaxy
Install the travel eSIM first, and know which line is which. Labelling them Home and Travel makes the rest quicker, and menu wording below is quoted from Apple, Google and Samsung.
Step 1. Turn data roaming on or off on an iPhone
With one line, Apple’s path is Settings, Cellular, Cellular Data Options, then Data Roaming, and the same switch is how you disable data roaming. With two lines, go to Settings, Cellular, tap the number you want to change, then Cellular Data Options and Data Roaming, and set each line separately.
Our eSIM for iPhone guide covers the rest of the iPhone setup, from model support to Dual SIM.
Step 2. Point iPhone cellular data at the travel line
Go to Settings, Cellular, Cellular Data, and tap the travel line. Leave Allow Cellular Data Switching off while you are traveling. Apple’s iOS 26 prompt, Turn On Travel eSIM, makes the same choice for you if you pick Travel eSIM and Current eSIM.
Step 3. Set roaming on a Google Pixel
Open Settings, tap Network & internet, then SIMs, choose the SIM, and find Roaming. Under Your primary SIMs, set Mobile data to the travel eSIM, and turn off Automatic data switching.
Google notes that the available mobile network settings vary by phone and Android version, so the order of options may differ on other Android devices.
Step 4. Set roaming on a Samsung Galaxy
Samsung’s US support page gives Settings, Connections, Mobile networks, then the switch next to Data Roaming Access. To choose the data line, eSIMply’s Galaxy help uses Settings, Connections, SIM Manager, then Mobile Data.
Samsung warns that the steps may differ depending on your carrier, and Galaxy labels change between One UI versions. Trust the wording on your own handset if it differs from ours.
Step 5. Check mobile data usage on each line
On iPhone, the Cellular Data screen shows which line carries data, and Apple lists usage under the Cellular Data heading. If the travel line connects but nothing loads, work back through our activation checklist: line on, chosen for data, data roaming on.
How to avoid roaming charges that catch travelers out
Leaving the home line free to roam because the travel eSIM is supposed to handle data.
Only one line carries data at a time, yet the home line can still run up charges through calls, texts and data switching. Apple’s travel eSIM page warns you might still incur roaming fees from your home eSIM with both lines on, and AT&T lists background apps and Wi-Fi calls to non-US numbers among the things that trigger its daily fee.
To avoid data roaming charges, switch Data Roaming off on the home line, keep data switching off, and choose the travel eSIM as your data line. If you do not need your number on the trip, turn the home line off entirely.
On board, your phone may connect to a satellite network run by the airline or ship, and the European Commission says those services sit outside Roam Like At Home and usually carry high surcharges. Your Europe advises switching roaming off or using flight mode while on board.
Apple’s Dual SIM article notes that if data roaming is on for the number that uses cellular data, your voice-only number disables Visual Voicemail and MMS. Expect picture messages and visual voicemail on your home number to stop until you change the setup back.
Coming home with the wrong line on
On iOS 26 and later, Apple says your iPhone turns the travel eSIM off and your home SIM back on when you return, depending on your country or region. If that does not happen, go to Settings, Cellular, make sure Turn On this Line is enabled for your home line, and turn off any travel line you no longer need.
Then put your home line’s data roaming back to how your carrier expects it. Leaving it off at home can block partner coverage your domestic plan includes.
Data roaming settings for international travel, trip by trip
Rows are situations, and columns are the two switches that matter plus the line that should carry your data. Each setting follows the guidance cited above.
| Your situation | Home line data roaming | Travel eSIM data roaming | Line carrying data |
|---|---|---|---|
| Abroad, travel eSIM, home number kept for calls | Off | On | Travel eSIM, with data switching off |
| Abroad, travel eSIM only | Line turned off | On | Travel eSIM |
| Abroad, roaming included or carrier pass bought | On | No travel eSIM | Home line |
| EU plan traveling inside the EU | On (Roam Like At Home) | Usually not needed | Home line |
| Abroad, no allowance and no pass | Off | No travel eSIM | Wi-Fi only |
| On a plane or ship | Off, or flight mode | Off, or flight mode | Onboard Wi-Fi |
Stay connected abroad with an eSIMply travel eSIM
eSIMply sells travel eSIMs, so this part is about our own product. Everything above applies whichever provider you choose, and the switches work the same whoever made the profile.
Our setup follows the pattern on this page: install the eSIM before you fly, then on arrival turn the line on, make it your data line and switch its data roaming on. The QR code arrives by email as soon as you order, no ID is required, and support runs by chat or email around the clock if a line will not connect.
Screen-by-screen steps for iPhone and Android sit on our installation guides page, and our explainer on how an eSIM works covers the profile itself. Country guides such as Japan and Italy compare providers destination by destination.
Data roaming questions people ask most
Most questions about data roaming come down to whether to leave it on, what it costs, and whether it affects calls. The answers below cover those, plus the travel eSIM cases most guides skip.
Turn off data roaming on your home line if your plan has no international data and you have not bought one of your carrier’s international plans, because that is what stops data roaming fees abroad. Turn on data roaming if your carrier includes roaming, you bought a daily pass, or the line is a travel eSIM.
With a travel eSIM and your home line both active, set each line separately: on for the travel eSIM, off for the home line.
Roaming happens when your phone leaves your home network’s coverage and your mobile device connects to another carrier’s network instead. With data roaming on, you stay able to access data services outside your carrier’s coverage, apps behave as they do at home, and your service provider bills that mobile data usage under its roaming terms.
Verizon says background data alone can start a paid TravelPass day once data roaming is on, so a phone sitting in a pocket can still trigger additional charges.
In your home country the setting only matters when you leave your carrier’s coverage area, so leaving it on is mostly a question of what your plan says about partner networks. Before international travel, decide on purpose: turn it off on the home line unless your carrier includes roaming or you have bought a pass.
Not automatically. AT&T and Verizon both sell a daily international travel plan on top of unlimited plans, and at both the cost of roaming is $12 per line per day in most destinations.
Inside the EU, Roam Like At Home covers unlimited contracts, but Your Europe explains that your operator may cap roaming data using a formula tied to your monthly subscription price, and must tell you the limit in advance. Whoever your carrier is, AT&T, Verizon, T-Mobile or a network provider outside the US, check with your service provider before you travel to avoid extra charges.
No. The switch controls mobile data services only, so the rest of your mobile service carries on, and AT&T confirms you can still make calls and send texts with data roaming off.
Calls and texts on a foreign network can still be billed under your carrier’s roaming terms, and the GSMA notes that roaming customers pay for calls they receive as well as calls they make.
Yes. You can access the internet over Wi-Fi, through a travel eSIM whose own data roaming is switched on, or with a local SIM card bought at your destination. Hotel or cafe Wi-Fi will keep you connected without incurring any roaming charges.
AT&T’s advice for avoiding unintended data use abroad is to put your phone in airplane mode and turn Wi-Fi back on. It also says to turn Wi-Fi Calling off, since a Wi-Fi call to a number outside the US triggers its daily fee.
For a travel eSIM, usually yes. eSIMply’s installation guide tells you to turn Mobile data and Roaming ON for the eSIM once you arrive, and Apple’s fix for a travel line showing No Service is to make sure Data Roaming is on for that number.
Switching it on for the eSIM does not switch it on for your home line, because iPhone and Pixel keep a separate setting for each line. If you are new to eSIMs, our guide to what an eSIM is covers the basics.
Mobile data, or cellular data on iPhone, is the main switch for mobile broadband over the cellular network. Data roaming is a second permission that decides whether that data may run over networks outside your carrier’s coverage. A travel eSIM needs both on for its line.
Roaming does not change how much data an app uses, so a map or a video call will consume data at the same rate abroad as at home. What changes is the price, and on pay-per-use rates roaming charges can add up quickly: AT&T’s rate is $2.05 per MB.
Both iPhone and Pixel show data usage per mobile app in settings, so you can check which apps are heavy and switch them off before using mobile data abroad on a metered data plan.
There are three ways to avoid roaming fees: a roaming allowance or pass from your carrier, a travel eSIM with your home line’s data roaming turned off, or Wi-Fi only. Our comparison of eSIM vs physical SIM covers the local SIM card option.
Whichever you choose, keep data switching off and watch background app data, since background use can start daily-pass charges and cause unexpected data roaming.
No. A virtual private network (VPN) encrypts your traffic, but the data still travels over the wireless network, so it counts as data use on whichever line carries it. Your network provider bills that data exactly as it would without the VPN.
Cellular iPad models are a mobile device like any phone, with the same switch, reached through Settings, Cellular Data, then Cellular Data Options and Data Roaming. Apple says an iPad with an eSIM can also browse cellular data plans from select carriers, which it describes as a way to stay connected in over 190 countries, regions and territories.
Data roaming means the mobile internet part of roaming, while international roaming covers calls and texts too. Google defines the Pixel setting by leaving your carrier’s coverage area, wherever that happens, so the same switch also covers domestic roaming.
Where these facts come from
Every setting name on this page was read on the handset maker’s own support documentation in September 2026, and every price comes from the carrier’s own page. Where two official pages word the same switch differently, both readings are given.
- Definitions and iPhone paths come from Apple’s cellular data settings guide, roaming options article, travel eSIM article, Dual SIM guide and Dual SIM with eSIM article.
- Android paths come from Google’s Pixel Phone Help, Connect to mobile networks and How to use dual SIMs, and from Samsung US support.
- How roaming works and how roaming charges are billed comes from the GSMA.
- Carrier charges come from AT&T’s International Day Pass support article, AT&T pay-per-use rates, AT&T’s international use guide and Verizon’s TravelPass FAQs.
- EU and UK rules come from the European Commission, Your Europe and GOV.UK.
- eSIMply’s setup steps come from our own installation guides and helpdesk.
- Questions came from the People Also Ask box for this search. No forum post is quoted, because no comment body could be retrieved.
eSIMply runs its own travel eSIM service, so one of the products mentioned on this page is ours. None of the settings above change based on who you buy from.
We may receive commission if you buy through our links. That does not affect which switch this page tells you to flip.
Jamie has worked in telecommunications for more than 8 years across mobile, SMS, eSIM, apps, and adjacent technology. He now writes for eSIMply as the tech content writer, analysing the top eSIM providers and breaking down what travellers actually need to know.
While we do our best to ensure accuracy, prices and plan availability are subject to change. Last updated by Jamie Cole.
