What are Piggyback Phone Networks? UK MVNOs explained

There are many mobile operators in Britain, but many of them ‘piggyback’ on the networks of the big four – EE, O2, Three and Vodafone.

Who uses which network and what are the benefits of using a piggyback service? Here’s everything you need to know about them.

What is a piggyback telephone network?

Setting up a mobile telephone network is no easy feat. You need channels and other expensive infrastructure that cost enormous amounts of money, so it’s not possible for many companies to create these.

As a way to offset some of these costs, the network owners let others pay to use them. That’s why these are called piggyback services.

However, officially they are known as MVNOs, which stands for Mobile Virtual Network Operators.

What are the main networks in Britain?

There are four main networks:

In 2023, Three and Vodafone announced their intention to merge, but the process to approve and complete this will take some time, if it happens at all. So at the moment we still have four major providers in Great Britain.

Plus, thanks to MVNOs, there’s a much wider choice of where to get a SIM card, and often at a much lower cost than using one of the main four.

Here’s an overview of the main MVNOs in the UK and which of the ‘real’ networks they use. This is important because coverage varies, and if you want 5G, it’s wise to check whether it’s available where you live, work and regularly travel.

These are the main MVNOs in Great Britain.

Which MVNOs use the EE network?

Which MVNOs use the O2 network?

Which MVNOs use the Three network?

Which MVNOs use the Vodafone network?

Benefits of a piggyback mobile operator

While it may seem obvious to buy a SIM card directly from EE, O2, Three or Vodafone – the people who actually own the networks – there are some good reasons to choose a piggyback operator.

Because these MVNOs don’t have the additional costs of maintaining and improving the networks, they can offer their customers some serious benefits.

That’s why one of the features of piggyback providers is that you can usually get cheaper plans by signing up with them. Especially if you keep your existing phone and opt for a SIM-only subscription.

For example at the time of writing O2 is offering a SIM-only deal that includes unlimited calls, unlimited texts and 12GB of data for £17.99 per month, and that’s a two-year contract.

Alternative, Giffgaff (which uses the O2 network) offers the same deal, but with 40GB of data, for £15 per month and you can cancel at any time as it’s a monthly rolling contract. Clearly much better value.

Artur Tomala / Foundry

Artur Tomala / Foundry

Artur Tomala / Foundry

As the rates mentioned above show, MVNOs are free to offer more flexibility in their plans, increasing the chances that you can find one that suits your needs. One of the biggest benefits is that many plans offer ongoing monthly plans where you can stop paying at any time and switch to another provider if you come across a better deal.

You may still want to sign up for a longer contract, but at the other end of the scale there are pay-as-you-go plans, where you only pay for the data, calls and texts you make. This is the kind of freedom you don’t usually get with any of the big four networks.

If you’re traveling or want to try out a different network, the monthly rolling options are low risk because you’re not tied into a long contract. This can be particularly useful if you have just moved to a new location and find that your existing network coverage is not very strong there.

Disadvantages of having a mobile operator on your back

One thing you don’t get are the bonus features that are often used by major networks as an incentive to choose them instead. This includes free subscriptions to streaming services, discounts at stores or other entertainment benefits.

For example the Three+ The incentive program includes deals at Cineworld, Caffe Nero, Nike, Uber Eats and more, plus access to pre-sale tickets to concerts and festivals. O2 Priority is very similar.

Artur Tomala / Foundry

Artur Tomala / Foundry

Artur Tomala / Foundry

Another thing is that you may also notice that the range of phones available on major networks’ plans is better than on MVNOs. So if you think you might want to buy a new phone on your plan, then it’s worth checking a few different networks before signing up.

Ultimately, the support is also worth keeping in mind. To offer a cheaper service, a piggyback operator may not have telephone support. If you need help, you may need to fill out an online form. GIFFGaff, for example, is highly dependent on the support of its own community.

There are two different services that are MVNOs, but also sub-brands of the larger networks. These are Smarty, part of Three, and Voxi, part of Vodafone. Both have some great offers, so you can get the best of both worlds if you want to use the Three or Vodafone networks.

Why choose a piggyback mobile operator?

For most people, getting a SIM card from Lebara, Tesco or one of the other piggyback providers will save a lot of money and give you more freedom to switch whenever you want.

You may miss out on the various incentives offered by major networks, but the money you save is almost certainly worth more. Notably, you get the same coverage and speeds (many MVNOs now offer 5G as standard) and roaming options.

As with any phone plan, you should check the latest offers from both the network operators and those who connect to them. And as you’d expect, we’ve rounded up the best SIM-only deals to save you time.

For more information, check out our overview of the best phone networks and the best Pay As You Go networks in the UK.