Searching for a mobile network that uses Three?
In this guide, we’ve ranked the best Three mobile virtual networks operators (MVNOs) you can join at the moment.
After, we’ve explained some key things to consider when choosing a Three mobile network to buy a SIM plan from.
Best Three-powered mobile networks
1. Smarty
Smarty is the only Three piggyback network that is owned by Three directly.
In our experience, MVNOs that perform the best are owned by their parent network, rather than merely buying network access from them.
For example, Vodafone owns VOXI, O2 owns giffgaff, and Three owns Smarty.
Using this network, we get fast 5G speeds and really good coverage from testing we’ve performed in the West Midlands and London.
We think Smarty is the best Three MVNO to choose, if you’re most concerned about getting the best coverage and overall performance.
Smarty is very easy to get started with, and their pay as you go SIM plans have very low monthly costs.
The only downside to Smarty is their roaming allowances aren’t the best. However, this is the case with most Three MVNOs at the moment.
2. iD Mobile
Compared to Smarty, iD Mobile is a more premium option.
Their monthly costs aren’t always as competitive on pay as you go plans. However, their prices are some of the lowest on the market on pay monthly SIM contracts, if you don’t mind committing for 12 months or more.
iD Mobile also has a really large range of phone contracts to choose from. They can be a good choice if you want the latest iPhone or Samsung Galaxy device on a contract, with nothing upfront.
Also, iD Mobile has the best roaming allowances of any Three MVNO.
They have a really good range of inclusive roaming destinations, including less common countries like Azerbaijan. Plus, they give you up to 30GB of data to use overseas each month – a lot more than you get with Smarty, or when buying a Three SIM directly.
iD Mobile supports eSIMs and WiFi calling, and their network also performs very well. Although, we don’t think their 5G speeds are quite as fast as what you get with Smarty at the moment.
3. Honest Mobile
Honest Mobile is a SIM-only provider with two types of tariff.
If you want to use the Three network, you’re after one of their Classic SIMs.
You get the choice of a 30-day or 12 month contract, which is good, but the range of data limits on offer is a bit limited.
After the 10GB plan, if that’s not enough data, it jumps straight to unlimited data, which can be a bit expensive.
The unique thing about Honest Mobile is rather than having mid-contract prices rises, they actually give you a discount if you stay with them over the long term.
They currently drop your bill by 5% a year, applied each month, up to a total of 30% off the original price.
We just wish the range of plans Honest had available was a bit larger, in case you want 50GB or 100GB of data for example.
4. Three
If you want to use the Three network, it’s also worth considering buying from them directly, because their deals are so cheap.
Three is the cheapest big four network at the moment, despite offering the UK’s fastest 5G speeds.
They have a really good range of SIM-only deals, handset plans, and mobile broadband tariffs to choose from, no matter whether you’re after a cheap long-term contract, or want a more flexible month-to-month option.
Three’s roaming allowances aren’t the best, because their fair usage limit is just 12GB of data a month, no matter how high your actual data limit is.
However, if you want fast 5G, with really good coverage, and solid calling performance as well, we think Three is definitely worth looking at.
What you need to know about buying a Three network SIM
In this section, we’ve explained some key things you need to know when buying a SIM on the Three network.
Which mobile networks use Three?
Currently, the following mobile networks piggyback off Three infrastructure:
- Smarty
- iD Mobile
- Honest Mobile
- Superdrug Mobile
- Yayzi
- Onebill
The first three networks are the only ones we would consider using at the moment, as the remainder are smaller, less established companies, with less of a focus on providing price-competitive SIM deals for consumers.
What are the pros of the Three network?
There are a few different things that really stand out about the Three network:
- They have the fastest average 5G speeds in the UK, and really good coverage as well. Unlike Vodafone and EE, they don’t put speed caps on any of their plans.
- They often offer some of the cheapest prices on the market, no matter whether you buy from Three or use one of their MVNOs.
- Three has a good range of MVNOs to choose from, including one they own directly (Smarty).
What are the cons of the Three network?
There are also some downsides to Three and its MVNOs that it’s worth keeping in mind.
- While their 4G coverage is good, some other networks like EE can perform better in this area.
- Three and its MVNOs do not tend to offer very strong roaming allowances, except for iD Mobile.
- Three and its MVNOs’ plans tend to be quite basic, with little in the way of extra benefits or free gifts included compared to Vodafone, O2, or EE.
How other networks compare to Three
If you’re not decided on using the Three network, you might be wondering how other networks and their piggyback providers compare.
- EE offers better 4G speeds and coverage than Three, but often has speed limits of 100 Mbps on their tariffs, unless you pay for a more expensive unrestricted plan. They also don’t have as good a range of pay as you go SIM deals to choose from, although their MVNOs, such as 1pMobile, have a better selection.
- Vodafone offers similar but slightly lower average 5G speeds than Three, and have speed caps on some of their plans. They generally include more extras and benefits on their tariffs, such as discounts on Vodafone home broadband.
- O2 has much worse 5G speeds and coverage than Three, though their international fair usage limits are higher, and their tariffs are normally more flexible. You can essentially build your own tariff from scratch if you buy from O2 directly. This network is price-competitive with Three, especially on their giffgaff MVNO, but O2 doesn’t have as many different piggyback networks to choose from.
Other non-Three MVNOs worth considering
Apart from Smarty, iD Mobile, and Honest Mobile, there are some other non-Three MVNOs you might also want to consider if you want a cheap SIM-only deal.
- VOXI (Vodafone) offers fast 5G, with cheap pay as you go SIM plans, and other good-to-have benefits, such as unlimited social media usage, separate from your monthly data limit.
- 1pMobile (EE) offers really strong coverage in remote areas on 4G, along with fast 5G, though they can be a bit expensive.
- Tesco Mobile (O2) offers a great range of SIM-only and pay monthly phone contracts, and unlimited EU roaming (up to your data limit), though their 5G isn’t the fastest since they use the O2 network.
Conclusion
This is the end of our guide to mobile networks that piggyback off Three infrastructure.
In summary, we generally recommend Smarty if you want a flexible pay as you go SIM on the Three network, or iD Mobile if you want to save money by entering into a longer-term contract.
If you’re not sure which Three mobile provider to choose, feel free to ask for advice in the comments, and we’ll reply as soon as we can.
About the author
Tom is the founder of Green Smartphones. You’ll find him writing about phones on the Green Smartphones blog, or talking about SIM deals and mobile networks on our YouTube channel. He’s the Android expert on the team – currently using a Google Pixel 9, recently upgrading from a very long-suffering Note 20 Ultra. When he’s not working on Green Smartphones, you’ll find him playing football or hiking.