UK roaming in the USA vs an eSIM: what it costs

UK roaming in the USA costs about £7 to £8 a day per phone on most UK networks as of November 2026, unless your plan already includes the US. Over a week or two, that adds up quickly, especially for families. For most trips, a travel eSIM for data, with your UK SIM kept on for texts, costs less overall.

You're probably here because your trip is booked and you've just remembered the phone bill. The catch with roaming in the USA isn't that it's hard: your phone simply connects when you land. It's that the charge is daily and per phone. Vodafone, for example, raised its pay monthly charge for the US zone to £8 a day from 14 April 2026.

Below: what each big UK network charges, and what that comes to over a real trip. Then the plans that already include the US, a four-question check, and the settings that stop you paying twice.

Does my UK phone work in the USA?

Yes. Almost every UK phone works in the USA, because US networks run on the same 4G and 5G standards. When you land, your phone joins a US partner network on its own. Whether it costs you anything depends on your plan, not your phone.

Most UK plans treat the US as a "rest of the world" destination, outside the European roaming zones. That means one of three things happens:

• Your plan includes the US. You use your normal allowance at no extra cost. Only some plans do this.
• A daily charge kicks in. The first time you use your phone abroad that day, your network adds a fee. Some networks do this automatically.
• You need to add a bolt-on or pass first. Without it, roaming may be blocked or charged at higher pay-as-you-go rates.

The first job, before you compare anything, is to find out which of these applies to you. Open your network's app, look for "roaming" or "travel", and check the US. It takes two minutes, and the answer decides the rest.

How much does roaming in the USA cost on each UK network?

As of November 2026, Vodafone charges £8 a day and O2 £7 a day with its Travel Bolt On. Three charges £5, £7 or £8 a day, depending on your plan and when you joined. EE's prices depend on the plan. All of these are per phone, for each day you use it.

Here are the published figures we checked on 1 November 2026.

A few details in that table matter more than the headline price:

• O2's speed cap. At 2 Mbps, maps, messaging and music work fine, but video calls and uploads can be slow.
• Three's passes. Over 7 or 14 days, a pass works out cheaper than paying the daily charge every day. It's still per phone.
• Join dates. On Three in particular, two people on what looks like the same plan can pay different daily charges, depending on when they joined or upgraded.

How do UK daily roaming charges actually work?

A daily roaming charge is a flat fee your network adds for each day you use your phone abroad. It usually starts the first time your phone makes a call, sends a text or uses data that day. Even one background app refresh can count. The fee covers your normal allowance for that day.

Three things catch people out:

One small action starts a paid day

On O2, the Travel Bolt On charge covers 24 hours from your first use, and it's triggered by making a call, sending a text or using data. Receiving calls and texts doesn't trigger it. That's useful: you can leave your UK line switched on to receive bank codes, as long as you don't send anything and data roaming is off.

Data is the risky one. If data roaming is on for your UK line, apps refresh in the background the moment you land. Email syncs, photos back up, and the daily charge starts before you've touched the phone.

It's per phone, not per account

Every phone on a family account pays its own daily charge. If four of you travel and all four phones roam, that's four charges a day. The table in the next section shows how fast that grows.

Spend caps may not cover it

O2 says its Travel Bolt On isn't part of your Spend Cap. If you rely on a cap to keep the bill under control, check how your network treats roaming charges before you assume they're blocked.

Is an eSIM cheaper than roaming in the USA?

For most trips longer than a couple of days, yes. Roaming adds a fee every day, on every phone, while a travel eSIM is one price for the whole trip. The gap widens with each extra day and each extra phone. For a day or two, roaming can be the cheaper or simpler choice.

To show the scale, here's our own arithmetic, using the published daily charges above. It assumes you use the phone every day of the trip, which is what most people do.

These are our calculations from the networks' published prices (checked 1 November 2026), per phone. They're not quotes from the networks.

To compare, open the United States plans and pick one that fits your trip length and data needs. Each plan shows its full price before you pay, and that price doesn't grow with the number of days you use it.

Three worked examples

These are hypothetical trips, to show how the sums work.

Suppose you're a couple on Vodafone, going to Florida for 10 days. Neither plan includes the US. At £8 a day, that's £80 each, £160 for the two of you. Two travel eSIMs, each sized for ten days of maps, messaging and photos, are two one-off prices. You'd compare those against the £160.

Suppose you're a family of four on Three, two weeks in California. Using the daily charge at £8, that's £112 per phone and £448 for four phones. Buying four 14-day passes instead is £60 each, £240 in total. Four eSIMs, or fewer if the children only need Wi-Fi, would be compared against the £240, not the £448.

Suppose you're on O2, flying to New York for a two-day work trip. At £7 a day, that's £14, with calls to UK and US numbers included. Here roaming is hard to beat for simplicity. It's also the better choice if you need lots of normal calls.

The pattern: the longer the trip and the more phones, the bigger the difference.

Which UK plans already include the USA?

Some UK plans include roaming in the USA at no daily charge. As of November 2026, these include O2's Travel Inclusive Zone, which comes free with selected Plus plans, and Vodafone's Xtra Global Roam plans. If you're on one of these, you may not need to buy anything.

What the networks' own pages say:

• O2: The Travel Inclusive Zone covers 27 destinations, including the USA, with unlimited minutes, texts and data, capped at 2 Mbps. It comes free with selected Plus plans, and Volt and Plus customers can add it. Pay As You Go and 30-day SIM-only plans can't get it.
• Vodafone: Global Roam on pay monthly covers 84 destinations in Zones A, B and C, including the USA. Vodafone says its Xtra Global Roam plans include all of them.
• Three: Three says plans joined or upgraded on or after 22 June 2025 have Go Roam built in, but check that this covers the US on your plan. Three's destination list puts the US in "Go Roam Around the World".
• EE: Some plans are reported to include the US. Check the My EE app for yours.

If your plan includes the US and the speed cap doesn't bother you, roaming is the simplest choice. You'll have your normal number for calls and texts, and there's nothing to install.

What do you keep and lose with a travel eSIM?

With a travel eSIM you keep your UK number, WhatsApp and bank texts, because your UK SIM stays in the phone. What you don't get is a phone number on the eSIM itself: travel eSIMs, including ours, are data only. Normal calls still go through your UK line at your network's rates.

The difference that matters for most people is normal phone calls. If you need to ring US restaurants, hotels or rental car desks on a normal number, you can still do that from your UK line. Everything else, from maps to messaging and video calls, runs over data.

The four-question roaming check

This is our own checklist. It's not an official standard, but it answers the "roam or eSIM?" question in four steps.

1. Does your plan include the US? If yes, check the speed cap and fair-use limit. If those suit you, use roaming and stop here.
2. How many days will you use your phone? One or two days: roaming is usually fine. Three or more: keep going.
3. How many phones are travelling? Multiply your network's daily charge by days and by phones. That's the real roaming cost.
4. Do you need lots of normal phone calls? If yes, keep your UK line ready for calls. Either way, compare your step 3 total with an eSIM for data.

If step 3 comes out well above the price of an eSIM for each phone, the eSIM is the better deal. If it's close, roaming's simplicity may be worth the difference.

How to set up a travel eSIM and keep your UK number

You can set it up in about ten minutes at home, and it needs Wi-Fi. The idea is simple: the eSIM does all the data, and your UK line stays on for texts with its data roaming off. That way the UK daily charge never starts.

At home, a few days before you fly

1. Check your phone. Use our phone check to confirm it supports eSIM. If it came from a network before December 2021 or second-hand, make sure it's unlocked.
2. Choose a plan. Pick one that covers your trip length, with some data to spare. If you're also visiting Canada or Mexico, see the section below first.
3. Install it on Wi-Fi. Follow the iPhone guide or the Android guide. It takes a few minutes.
4. Rename the line, for example to "US data", so it's easy to spot in Settings. How to rename it.
5. Leave it switched off. With kimsim, the plan only starts when the eSIM first connects to a network in the US, so installing early doesn't use any days. When plans start.

When you land

1. Switch on the eSIM line and set it as your mobile data line. How to choose your data line.
2. Turn on Data Roaming for the eSIM line. Your phone sees a travel eSIM as roaming, so it won't connect without this. You won't be charged roaming by us: the switch just lets the phone connect. Why it's needed.
3. Turn off Data Roaming for your UK line. This is the step that stops the daily charge.
4. On iPhone, leave "Allow Mobile Data Switching" off, so the phone doesn't quietly fall back to your UK line.
5. Keep the UK line on for receiving texts and, if you need them, calls.

If you see signal bars but no internet, wait two minutes, then restart the phone. That fixes most first-connection problems. More in no signal on arrival.

Will I still get bank texts and WhatsApp messages?

Yes. Because your UK SIM stays in the phone, texts to your UK number, including bank and app verification codes, still arrive. WhatsApp, iMessage and FaceTime are linked to your account, not the line carrying the data, so they keep working on your usual number over the eSIM.

Some practical points:

• Receiving texts on your UK line is normally free. On O2, receiving calls and texts doesn't trigger the daily charge, according to O2's own page.
• Sending a normal text or making a normal call from your UK line may trigger your network's daily charge. Reply on WhatsApp instead where you can.
• WhatsApp calls to family at home use data from the eSIM, not your UK allowance.

For the full picture, see our guides to calls and texts and WhatsApp with a travel eSIM.

How much data do you need in the USA?

Many travellers use around 3 to 7 GB a week for maps, messaging and some social media. US trips can be at the higher end, because of long drives with navigation, ride-hailing apps and plenty of photos sent home. Video calls, streaming and hotspot use need much more.

As a rough guide for a week in the US:

These are rough estimates. Real use depends on your apps and settings. Our guide to how much data you need breaks it down by activity.

If you'd rather not count, an Unlimited plan gives you a daily full-speed allowance, then keeps you connected at 1 Mbps until the next day starts. That's enough for messages, maps and music, though not HD video. If you're using your phone as a hotspot, test it on day one, because hotspot support depends on the network.

Common mistakes that cost UK travellers money

Most surprise roaming bills come from a few settings, not from heavy use. These are the ones to watch:

1. Leaving Data Roaming on for your UK line. This is the big one. Background apps start the daily charge before you've even unlocked the phone.
2. Letting the phone switch data back to the UK line. On iPhone, "Allow Mobile Data Switching" can move data to your UK line if the eSIM signal drops. Keep it off.
3. Forgetting that every phone pays. A child's phone with data roaming on pays the same daily charge as yours.
4. Assuming a spend cap protects you. O2 says its Travel Bolt On isn't included in Spend Cap. Check your own network.
5. Sending normal texts "just this once". On some networks a sent text starts a paid day. Use WhatsApp or iMessage over the eSIM instead.
6. Turning the eSIM on during a stop-over. If your plan covers more than one country, it may start early. For a US-only plan, keep the line off until you land in the US. More on plans starting early.
7. Deleting the eSIM to "fix" it. A deleted eSIM usually can't be reinstalled. Restart the phone first. If you've deleted it.

Going to Canada or Mexico as well?

A US-only eSIM won't work in Canada or Mexico, and your UK network may price those countries differently from the US. If your trip crosses a border, for Niagara Falls or a few days in Cancún, a North America plan covers all three countries on one eSIM.

Before you buy any multi-country plan:

• Check every country on your route is on the plan's list, including any you'll only pass through.
• Remember when it starts. A regional plan starts when it first connects in any covered country. How regional plans work.
• Look at the networks. They can differ by country, and the plan page lists them.

See the North America plan, or plans for each country below.

How we put this guide together

We checked each network's own roaming pages on 1 November 2026: Vodafone's out-of-bundle prices and travel pages, O2's Travel and Travel Inclusive Zone pages, and Three's roaming and destination pages. EE's pages didn't load for us, so EE figures come from a comparison site and are marked as such. The trip totals are our own arithmetic from those published prices. Facts about kimsim come from our help centre. kimsim sells travel eSIMs, including the US plans mentioned here.

If you're new to eSIMs, start with what an eSIM is, or see how roaming compares worldwide in eSIM vs roaming. For US-specific tips, read our eSIM for the USA guide.