Internet in the USA: how a European traveller gets mobile data

Why your EU plan behaves differently in the US

The EU's Your Europe portal explains that roam like at home covers the EU countries plus Iceland, Liechtenstein and Norway, and it also lists Moldova and Ukraine. Other countries are not covered by the regime, although the portal notes that many operators choose to extend their offers to some of them. The United States is one of those other countries, so whether your bundle works there, and at what price, is up to your operator rather than an EU rule.

The same page warns that roaming outside the EU and EEA can be expensive, especially for data, and advises checking your provider's prices before you travel. It adds a point for the flight itself: if the service on board runs over satellite, EU rules no longer apply and there are no price caps, so flight mode is the safe choice. If you are not going to use your operator's own US offer, switch off data roaming on your home line before departure, as shown in how to turn off roaming on your home line.

Three ways to get online

• A travel eSIM: a data-only plan you buy and install at home. It joins US networks as a visitor when you land, and your home SIM can stay in the phone for calls and texts.
• A US prepaid line: US carriers sell prepaid plans that come with a US number. Verizon, for example, says on its prepaid eSIM page that you can only activate it while you are in the US, and its app asks for your location to check.
• Wi-Fi only: hotels, cafés and some visitor centres. It can cover a city break with planned days, but on a road trip you lose maps, messages and bookings between one stop and the next.

The main difference between the first two is the number. A prepaid line gives you a US number for local calls; a data-only eSIM gives you no number at all, and you keep using your own through the apps. Snoozim's United States plans are data-only and connect to Verizon and AT&T, the two networks listed for them. For most visitors that is enough, because messaging, maps, ride-hailing and email all run on data.

Check the phone before you pack it

A travel eSIM or a US prepaid line only works on a phone that is not locked to your operator. On an iPhone, Apple's path is Settings, General, About: if the phone is unlocked, No SIM Restrictions appears next to Network Provider Lock. Android menus vary by brand, so follow how to check if your phone is unlocked, and confirm your model in the eSIM compatibility list. If it is locked, ask your operator about unlocking it well before the trip.

Then install the eSIM at home. Apple says the iPhone needs a Wi-Fi network or a hotspot to set up an eSIM, which is easier from your sofa than in an arrivals hall. A Snoozim eSIM arrives as a QR code by email and only starts counting when it first connects in the US. On the iPhone you pick which line uses data in Settings, Mobile Data, and from iOS 26 the phone may offer Travel eSIM Only or Travel eSIM and Current eSIM when the travel eSIM activates. Apple warns that with both lines on you might still incur roaming fees from your home eSIM.

Calls, texts and WhatsApp on a data-only eSIM

Having no US number does not mean losing yours. Apple says that if you keep both lines on, the capabilities of your primary line continue to work, and that if you use only the travel eSIM, FaceTime and iMessage stay on your home line. WhatsApp keeps your account and number and simply uses whatever data connection is active. Its help centre says voice calls use your internet connection rather than your plan's minutes, and suggests calling on Wi-Fi if you want to use less data.

Ordinary calls and SMS to your home number are a different matter: they reach you through your operator's roaming, at its prices. That matters for bank codes, which are covered in how to get bank SMS codes abroad. Wi-Fi Calling can help, but Apple says it depends on your carrier offering it and tells you to check availability and any fees with them; the details are in Wi-Fi calling abroad. For calling a hotel or a restaurant from the US, see how to call with a data-only eSIM.

Landing: the arrival app needs a connection

US Customs and Border Protection offers Mobile Passport Control, a free and optional app. Its page lists returning Visa Waiver Program travellers with an approved ESTA among those who can use it, along with US citizens, permanent residents and Canadian visitors. It does not replace your passport, and you still see an officer.

The connection is the detail that catches people out. In a CBP leaflet, the agency says cellular or Wi-Fi connectivity is required to send the information, but you can complete your profile without being connected. CBP adds that you can submit up to 4 hours before landing and that the submission stays active for 4 hours. The sensible order is to create the profile at home, have the eSIM installed and data roaming switched on for it, and send the trip details once the plane is on the ground. Airport Wi-Fi is the fallback if anything fails.

National parks and long empty roads

The US has large areas where no network reaches, and the National Park Service says so plainly. In Yellowstone, the park describes cellular service as extremely limited: towers at developed areas and near the North and West entrances cover the main sites, summer crowds can overload the network, and texting is the most reliable option. It lists free public Wi-Fi at the Albright Visitor Center, the Old Faithful Visitor Education Center and the West Yellowstone Visitor Information Center, and asks visitors to check their carrier's coverage before going.

Death Valley goes further: its directions page says there is no cell phone service along most park roads, calls GPS navigation to remote places notoriously unreliable and tells visitors to carry current paper maps. Joshua Tree says there is little to no cell service inside the park and recommends downloading the park in the free NPS app for offline use. Since our US plans use Verizon and AT&T, look at those two coverage maps for your route, and read phone signal in mountains and national parks before you head out.

How much data a road trip takes

There is no single figure, because the drive itself can cost almost nothing. Google says offline maps can guide you by car as long as the whole route is inside the area you downloaded, although you lose traffic information and alternative routes, and walking, transit and cycling directions are not available offline. Download each region on the hotel Wi-Fi the night before, as explained in how to use Google Maps offline, and see using your phone as GPS in a rental car for the car itself.

What fills the allowance is everything around the driving: music streamed in the car, video calls home in the evening, photo backups and passengers connected to your phone's hotspot, which all come out of the same eSIM. Count the days, decide which of those habits you will keep on mobile data and put them into the data calculator. City days are different again; internet in New York covers one. If you run short halfway across the country, a top-up goes onto the same eSIM, as described in how to top up a travel eSIM.