Three roaming in USA: charges, data plans and how it works in 2026

Three UK's roaming in the USA works through its Go Roam Around the World scheme and for pay monthly customers on eligible plans, the USA is included at no extra charge up to your 12GB roaming allowance. For PAYG customers or anyone who needs more data, the picture is different.

This guide covers exactly what Three charges for roaming in the USA, which plans include it, how to activate it, what to do when it stops working, and when buying a travel eSIM saves you money.

Does Three roaming work in the USA?

Three UK does offer roaming in the USA, and for most pay monthly customers it activates automatically when your phone connects to a US partner network. What's included and whether you pay depends on your plan.

• Three's Go Roam Around the World programme covers the USA as a roaming destination. If you're a pay monthly customer on a plan that includes Go Roam, your phone will connect to a US mobile network automatically when you land. Your UK number stays active, you can make and receive calls, send SMS, and use mobile data on your standard UK allowance up to the 12GB roaming cap.
• International roaming with Three also covers voice calls, SMS, and data, though the rates differ depending on whether you're on pay monthly or PAYG. Three's US roaming partner networks are AT&T and T-Mobile, which between them cover the vast majority of the country. In cities and along major interstate routes, connectivity is solid.

Roaming does not activate automatically on all plan types. PAYG customers need a data pack with a roaming allowance active before they travel. And regardless of your plan, your phone needs data roaming switched on in settings, that's a device-side toggle, separate from whether Three has enabled roaming on your account.

Read also: Mobile Internet in the USA for Tourists

Three roaming charges in USA

The charges you can expect for roaming in the USA with Three vary significantly depending on whether you're on pay monthly or PAYG, and whether you've used up your included allowance. Running out of your data allowance mid-trip and rolling onto standard rates is the most common source of unexpected roaming charges.

Pay monthly, included roaming

Pay monthly customers on plans that include Go Roam Around the World can use their UK plan's minutes and texts in the USA at no extra cost. Mobile data is included up to 12GB per month across all Go Roam Around the World destinations combined. Beyond 12GB, standard roaming rates apply:

At 10p/MB, running even 500MB over your limit costs £50. If you're heading to the USA for more than a week and use data regularly, check your monthly usage at home to gauge whether 12GB will cover the trip.

Go Roam Around the World passes

For customers who need more flexibility, Three offers standalone Go Roam passes for the USA. These are add-ons you buy separately useful for one-off trips, or for PAYG customers who want a fixed roaming cost rather than per-MB billing.

You can buy a Go Roam pass through the Three app or online before you travel. The pass covers your standard UK allowance of minutes and texts, plus mobile data up to the 12GB combined roaming cap. If you buy the 7-day pass at £30 and your monthly plan already includes Go Roam, check whether you actually need the add-on, some plans include the USA destination without requiring a separate pass purchase.

Three USA roaming plans and Go Roam explained

Three's roaming structure splits into two customer types: pay monthly and PAYG. The rules and costs are meaningfully different between them, so it's worth knowing which one applies before you travel.

Pay monthly

If you're a pay monthly Three customer on an eligible plan, the USA is a Go Roam Around the World destination included with your plan. Your minutes and texts work the same as at home. Mobile data counts against a shared 12GB roaming allowance across all Around the World destinations, this is a monthly cap, not a per-trip cap, so if you've already used roaming data elsewhere in the same month it reduces what's available for the USA.

Not every pay monthly plan includes Go Roam Around the World. Some older or lower-cost plans only cover Go Roam in Europe destinations. Check My3 or the Three app before travel to confirm whether the USA is included in your specific plan.

Speed during roaming is typically capped. Even on plans that advertise 5G at home, Three's USA roaming generally delivers 4G speeds. Don't plan around 5G connectivity in the USA. Hotspot tethering on the roaming allowance is restricted on some plans. The 12GB roaming data is generally for device use only, check your specific plan terms for tethering rules.

PAYG data packs with roaming allowance

PAYG customers on Three need an active monthly data pack to access roaming in the USA. Each data pack includes a roaming allowance alongside domestic data and 3,000 minutes and texts.

If you need more data during your trip, Three offers data add-ons you can buy while abroad:

The two unlimited add-ons are capped for roaming: 18GB over 14 days or 5GB over a single day. If you're working remotely or using your phone as a mobile broadband hotspot, those caps may run out faster than expected.

If you exhaust your PAYG allowance in the USA with no top-up, standard roaming rates kick in automatically: 10p/MB for data, 35p/min for calls to UK numbers, £1.40/min for calls to US numbers. These are the rates to avoid.

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Three data roaming USA: speed and coverage

Three's USA roaming uses AT&T and T-Mobile as its partner networks, two of the three largest US carriers, covering the vast majority of the population. For most destinations a Three customer would visit, signal quality is good.

• 4G LTE is available through both partners across major cities, airports, and interstate corridors. In practice, roaming speeds on partner networks are deprioritised relative to direct AT&T and T-Mobile subscribers, so expect real-world speeds in the range of 5–25 Mbps in urban areas. That's sufficient for Google Maps, WhatsApp, video calls, and standard browsing. Heavy data use, streaming video continuously, large file transfers, or using the phone as a hotspot for a laptop, will burn through the roaming allowance faster than domestic use.
• 5G roaming is not guaranteed. Three's roaming agreements with US partners may not extend to 5G access, even if your device is 5G-capable and the partner network has 5G coverage in that location. Plan on 4G.

Rural coverage follows the AT&T and T-Mobile footprint. Most tourist areas, national parks with visitor infrastructure, and smaller cities are covered. Very remote areas can have no signal regardless of carrier.

Hotspot tethering during USA roaming depends on your plan. PAYG data packs and some pay monthly plans do not include tethering on the roaming allowance. If staying connected on your laptop while travelling is important, verify this in the Three app before you travel or consider a travel eSIM from Yesim where hotspot is included on every plan.

Why Three roaming may not work in USA

A Three SIM that works perfectly at home can fail to connect, show no data, or drop calls in the USA for several distinct reasons. Each has a different fix.

• Roaming not enabled on the account. Some Three plans, particularly older contracts, have international roaming disabled by default. Open My3 or the Three app and check whether international roaming is active on your account. If it's off, you can usually enable it through the app.
• Data roaming switched off on the phone. Even with Three's roaming enabled on the account, the phone itself must have data roaming turned on. iPhone: Settings → Cellular → Cellular Data Options → Data Roaming → On. Android: Settings → Connections → Mobile Networks → Data Roaming → On. This is a separate step from account-level activation.
• Roaming allowance exhausted. The 12GB monthly roaming cap for Go Roam Around the World customers and the equivalent caps on PAYG packs are easy to hit if you're streaming, using maps heavily, or sharing a connection. Check usage in the Three app and buy a data boost before you run out rather than after, rolling onto standard roaming rates at 10p/MB is expensive.
• Wrong network selected. In rare cases, the phone may have manually locked onto a US carrier that Three doesn't have a roaming agreement with. Go to mobile network settings and set network selection to automatic. The phone should then pick up AT&T or T-Mobile.
• Plan doesn't cover the USA. Go Roam in Europe does not include the USA. If your plan only covers European roaming destinations, the USA requires a separate Go Roam pass or a plan upgrade. Check your plan tier in the Three app.
• Incompatible device. Budget phones and some older handsets may not support the frequency bands used by AT&T or T-Mobile. This is rare with flagships and most phones bought in the UK after 2019, but worth checking if you're travelling with an older or cheaper device.
• SIM activation issue. If you recently switched to a new Three SIM or eSIM and haven't made any calls or used data in the UK yet, the SIM may not be fully provisioned for international roaming. Make a short call or use a small amount of data on Three's UK network before travelling.

How to activate Three roaming in USA

Activating Three roaming before you travel takes less than five minutes and avoids every problem described above. Do it at home with Wi-Fi available.

• Check your plan covers the USA. Open the Three app (or My3 or the Three app via browser) and navigate to your plan details. Confirm that Go Roam Around the World is included, or that you have a data pack with an international roaming allowance active.
• Confirm international roaming is enabled on your account. In the Three app under account settings, check that international roaming is switched on. If it's disabled, enable it before you travel.
• Buy a Go Roam pass if needed. If your plan doesn't include the USA, or you're a PAYG customer without an active data pack, buy the appropriate pass in the Three app. The 7-day pass at £30 and the 14-day pass at £60 are the most practical for typical US trips.
• Enable data roaming on your phone. iPhone: Settings → Cellular → Cellular Data Options → Data Roaming → On. Android: Settings → Connections → Mobile Networks → Data Roaming → On.
• Set network selection to automatic. Make sure your phone isn't set to manual network selection, which could lock it to a carrier Three can't connect to. Automatic selection lets it pick AT&T or T-Mobile when you land.
• Test before you need it. Once you land, open a browser and confirm data is loading. Check your remaining allowance in the Three app. If connectivity is lost mid-trip, the app also lets you buy a data boost without needing a UK Wi-Fi connection.

Three roaming USA vs eSIM: which is better?

For a short trip where you're a pay monthly customer with Go Roam included, Three's roaming is hard to argue against, you're already paying for it. For longer trips, heavy data use, or PAYG customers, the math shifts towards a travel eSIM for the USA.

The clearest case for a travel eSIM is if you're on Three PAYG and heading to the USA for a week, the Around the World pass costs £30 and still caps data at 12GB, while a Yesim USA eSIM gives you 10GB for around £10–15 with hotspot included and no risk of rolling onto standard roaming rates. On a dual SIM phone, you can run both: Three SIM active for calls and SMS on your UK number, Yesim eSIM handling all mobile data.

For pay monthly customers with Go Roam included, the calculation is simpler, use Three for data up to 12GB, and if you need more or want unlimited data with guaranteed hotspot, add a Yesim eSIM for the surplus.

Read also: Top 12 Best eSIMs for United States

The bottom line

Three UK roaming works in the USA through Go Roam Around the World, using AT&T and T-Mobile as partner networks. Pay monthly customers with Go Roam included get 12GB of roaming data at no extra cost, enough for most short trips. PAYG customers need an active data pack with a roaming allowance, and standalone Go Roam passes cost £12.50 for 3 days, £30 for 7 days, or £60 for 14 days.

Standard roaming rates at 10p/MB apply once any allowance runs out, which is when bills get expensive fast. Activate roaming in the Three app before you fly, switch on data roaming on your phone, and check your remaining allowance during the trip. If you need more than 12GB, want a guaranteed hotspot, or want to avoid any risk of overage charges, a Yesim USA eSIM alongside your Three SIM is the most cost-controlled option.

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