Disclaimer: The prices and information presented on this page reflect a snapshot at the time of research and may change at any time without prior notice.
Aisha
04 March 2026
O2 is one of the most roaming-friendly networks in the UK. Free EU roaming up to 25GB, no surcharges reintroduced post-Brexit, and a reasonably clear set of options for going further afield. When you head to the United States, though, the picture gets more complicated. Depending on your plan, you might pay nothing extra, £7 a day, or stumble into pay-as-you-go rates that make a single day of Google Maps a serious bill item. This guide breaks down every O2 USA roaming option available in 2026, the one detail buried in the small print that frustrates more travellers than anything else, and when it makes more financial sense to pick up a US eSIM before you board.
O2's roaming setup is tiered by plan. European roaming is handled cleanly — O2 remains the only major UK network not reintroducing EU roaming charges, so your UK allowance works across 48 European destinations up to a 25GB fair use limit. The USA is a different tier entirely, sitting outside the Europe Zone and governed by separate bolt-ons and plan inclusions.
The key split is between customers on Volt and Plus Plans versus standard Pay Monthly customers. Volt customers (those bundling O2 mobile with Virgin Media broadband) and Plus Plan subscribers get the O2 Travel Inclusive Zone included at no extra daily cost. This covers 27 destinations outside Europe including the USA, with unlimited minutes, texts, and data — but with a hard speed cap of 2Mbps. O2 Ultimate Plan customers get the expanded Travel Inclusive Zone Ultimate covering 75 destinations, also at 2Mbps and with no extra daily charge.
For everyone else on a standard Pay Monthly plan, the O2 Travel Bolt On applies. This costs £7 per day (for the days you actually use it) and covers 75 destinations outside Europe including the USA, Canada, Australia, New Zealand, and Mexico. It includes unlimited minutes, texts, and data, again capped at 2Mbps. You need to activate it before you travel, either through the My O2 app or by texting TRAVEL to 23336.
Without any bolt-on or inclusive zone, standard pay-as-you-go roaming rates apply in the USA. These can reach £7.20 per megabyte for data — a single minute of standard-definition video at that rate costs more than the daily bolt-on fee. If you are on any O2 Pay Monthly plan and heading to the US without activating roaming first, check your account before departure.
Current options as of March 2026. O2 Travel Bolt On pricing and destinations are subject to change. Always verify in My O2 before departure.
Note: Calls to countries outside the UK and your destination are not included and will be charged at standard roaming rates regardless of your bolt-on.
Activate before you board, not after you land. O2 roaming in the USA is not automatic on most plans. Check the My O2 app under Travel or text TRAVEL to 23336 before leaving the UK. Arriving at JFK with data roaming on and no bolt-on active is the fastest way to generate a very large bill very quickly.
Your device must support 4G or 5G. US carriers have shut down 2G and 3G networks. If you are travelling with an older phone that does not support 4G LTE, it will not connect to any US partner network at all — calls, texts, and data will all be unavailable. Check device compatibility in My O2 before departure if you have any doubt.
The 2Mbps speed cap affects more than you expect. Two megabits per second is just about sufficient for standard-definition video on a small screen. It is not enough for reliable HD video calls, large map downloads, or fast navigation in unfamiliar cities. Streaming a podcast or using Google Maps works. A FaceTime call in decent quality or uploading photos at any speed does not.
Calls to third countries cost extra. The Travel Bolt On and Inclusive Zones include calls back to the UK and within the USA. If you call a European or non-US number from within the United States, standard international roaming charges apply on top of your daily rate.
Set a Spend Cap in My O2 as a safety net. Even with a bolt-on active, setting a monthly Spend Cap on your O2 account limits exposure to unexpected charges. The Travel Bolt On cost itself is excluded from the Spend Cap calculation, but other charges, including calls to third countries, are subject to it.
The £7/day only runs on days you actually use your phone. Unlike some day-pass systems that charge for the calendar day, the O2 Travel Bolt On only triggers on days you generate usage. A travel day where you connect to airport Wi-Fi and never touch mobile data will not be charged.
The Travel Bolt On at £7/day is competitive for short trips. Three days in New York costs £21 in roaming, and the unlimited data and calling allowance is genuinely useful for navigation, translation apps, and keeping in touch. For trips of a week or longer, the daily cost starts to add up, and the 2Mbps speed cap becomes increasingly frustrating when you want to stream something on a long train journey or make a video call home.
The speed cap is the detail that catches travellers off guard. O2's inclusive roaming across Europe has no such limit, so UK travellers accustomed to full-speed European roaming often arrive in the US expecting the same experience. The 2Mbps ceiling in the USA is a different product: workable, but noticeably slower for anything beyond basic browsing and messaging.
A US travel eSIM sidesteps both issues. It runs on local US network infrastructure — AT&T or T-Mobile — at full available speeds, with no artificial throttle. The cost for a defined data package is typically lower than O2's daily rate over seven days or more. Your O2 physical SIM stays active in dual-SIM mode for calls back to the UK and incoming texts. Most modern iPhones and a wide range of Android devices support this configuration without any additional hardware.
The 2Mbps speed limit is the defining feature of O2 USA roaming, and it matters more in the United States than anywhere else. American cities are large, distances between destinations are significant, and the practical reality of navigating Los Angeles, exploring national parks in Utah, or road-tripping from Miami to the Florida Keys involves sustained, real-world data use that 2Mbps handles poorly. Offline maps help, but they do not cover hotel bookings, restaurant lookups, translation, or anything that requires a live connection.
For Volt and Plus Plan customers who get the USA Inclusive Zone at no extra cost, the 2Mbps cap is still relevant — it is the primary reason UK travellers who do qualify for free US roaming still look at eSIM options for longer or more data-intensive trips. The free roaming is genuinely useful for a long weekend in New York or a work trip to San Francisco. A two-week road trip through multiple US states is a different calculation.
The dual-SIM setup makes the eSIM approach clean and simple. The O2 SIM stays active and available for calls and UK-number texts. The eSIM handles US data at full AT&T or T-Mobile speeds. Install the eSIM United States before leaving the UK, switch data to it on arrival, and leave mobile data off on the O2 SIM. No store visits, no physical SIM swap, no dependence on finding Wi-Fi for Google Maps in an unfamiliar city.
For standard Pay Monthly O2 customers, the O2 Travel Bolt On costs £7 per day for days you actually use your phone in covered destinations including the USA. Volt and Plus Plan customers get inclusive roaming in 27 destinations including the USA at no daily charge. Ultimate Plan customers get inclusive roaming across 75 destinations. Without any bolt-on or inclusive plan, standard pay-as-you-go rates apply and can reach £7.20 per megabyte for data.
All O2 USA roaming options, including the Travel Bolt On and the Inclusive Zone plans, cap data speeds at 2 megabits per second. This is sufficient for basic browsing, messaging, and standard-definition video on a phone screen. It is not enough for HD video calls, fast app loading, or consistent performance with data-heavy apps. UK travellers accustomed to full-speed European roaming on O2 should be aware of this difference before relying on O2 for data-intensive use in the US.
Yes. O2 roaming in the USA is not automatic. You must activate it through the My O2 app or by texting TRAVEL to 23336 before departure. Your device also needs to support 4G or 5G, as US carriers have decommissioned 2G and 3G networks. Arriving with roaming inactive exposes you to standard pay-as-you-go rates that can be very expensive.
Yes. The O2 Travel Bolt On and Inclusive Zone plans include unlimited calls back to the UK and to US numbers. Calls to third countries, for example calling a European mobile while you are in the US, are not included and will be charged at standard international roaming rates on top of your daily fee.
No. O2's USA roaming options cap data speeds at 2Mbps regardless of the local network's 5G availability. Even if the US partner network supports 5G in your location, your connection will be throttled to 2Mbps under all O2 roaming plans. A US travel eSIM connecting directly to AT&T or T-Mobile infrastructure is the way to access 5G speeds where available.
At £7 per day, a 14-day trip costs £98 in roaming charges. For that amount you get unlimited data capped at 2Mbps, plus calls and texts. Whether it is worth it depends on your data habits. Travellers who make regular video calls, stream content, or use navigation intensively across long distances often find the 2Mbps cap frustrating enough over a longer trip to make a dedicated US eSIM the better option at lower total cost and full speed.
Using a different carrier? See roaming options for other networks.
