O2 vs SMARTY: we compare their coverage, speeds and extras

✔ O2 provide more widespread call signal (3G/2G)

O2 operate their own network (though they’ve been bought out by Virgin Media’s parent) while SMARTY are a cheaper sub-brand of Three who piggyback off their network for signal.

You’ll get more reliable call signal on O2 in smaller towns and villages and even way out in the sticks. Total blackspots are more common on SMARTY, and O2 usually provide better indoor signal.

In terms of 4G data coverage (see 5G below) there’s not a massive difference. They both cover a similar percentage of the country’s landmass. And in urban areas there’s basically no difference.

It’s worth checking in your area regardless of the national picture. Use both networks’ coverage checkers here before joining. Don’t just check at home, but check at work or anywhere else you’ll use your phone.

Useful link: Read about SMARTY’s network improvements

✔ O2 have more 5G live locations than SMARTY

Despite being a budget network, SMARTY offer full access to Three’s 5G network on all plans. You get 5G in 484+ UK towns and cities on SMARTY, while O2 have a massive 750+ locations with 5G live.

But 5G is still only on a street by street basis. Generally, we found O2 are better at covering their locations than SMARTY, meaning you’ll get 5G in more areas and are more likely to stay connected to it on O2.

While there will be a lot of overlap in the locations both networks cover, you might only get 5G in your area on one rather than the other. It’s just that you’re more likely to get it in your area on O2.

The best thing to do is use their coverage checkers to see what each network’s 5G coverage will look like in your area.

Useful link: Updates on O2’s 5G rollout

✔ SMARTY provide typically faster 4G and 5G than O2

In testing, we didn’t find any evidence of a speed difference between Three and SMARTY, so we can compare Three’s results from independent network tests Opensignal against O2’s.

Their report shows typical 4G speeds of 30.7 Mbps on SMARTY and 16.8 Mbps on O2. While SMARTY’s results are almost twice as fast as O2’s, both are fast enough to stream HD video comfortably.

For 5G speeds, we compare results from Opensignal and Speedtest by Ookla. They measured average speeds between 228.4 Mbps - 248.16 Mbps on SMARTY’s hosts and between 80.57 Mbps - 92.3 Mbps on O2.

There’s a huge difference in typical speeds between the two networks and SMARTY provide peak speeds of up to 687.13 Mbps on SMARTY vs 214.2 Mbps on O2. SMARTY are the clear winner for speeds.

Useful link: SMARTY say they won’t slow you down

✔ SMARTY support more devices for WiFi calling

While O2 are typically better for indoor coverage than SMARTY, it’s still important that both include extra features in case you get indoor blackspots. Both networks offer WiFi calling and 4G calling.

These features let you connect to calls using WiFi or 4G signal. Both networks let you send SMS texts over WiFi and 4G too, and let you transfer from a WiFi call to a 4G call without it dropping.

The main difference is that SMARTY support more devices for WiFi calling than O2. While we found some phones not on O2’s list worked, they’re not guaranteed to. It’s easier to get WiFi calling to work on SMARTY.

If your phone is supported on either network then they’re both good choices for WiFi calling. It was annoying in our test to have to turn it on manually with O2, but other than that both schemes are pretty great.

Useful link: Our guide to the best WiFi calling networks

✔ O2 provide more hotspots Underground and across UK

These days, data signal is good enough to the point you can stay connected on the go without needing WiFi hotspots. But these are still handy for holding onto your data, especially when they work automatically.

SMARTY offer free WiFi on the Underground. It’s basically the same as Three’s, giving you free WiFi at ticket barriers and stations (but not the trains themselves). But you won’t be automatically logged in to these.

But O2 also offer another 16,000 free hotspots all across the UK. Currently 7000 of these hotspots will recognise your SIM after you’ve connected to them and will automatically log you in the next time you go there.

We tested it in real life for our review of O2. It’s a great way to save a bit of data, but the speeds you get can be slower than 4G/ 5G. Their scheme is a lot better than SMARTY’s for users not based in London.

Useful link: Our free WiFi hotspots guide

✔ O2 are a great choice for going to the EU and beyond

O2 are the only main network to keep their inclusive EU roaming in place. You can use your regular allowance in the EU on O2 for no extra cost (read our roaming guide here).

So you can use your UK minutes, texts and data while in their covered EU destinations at no added cost on both. But O2 let you use 25GB of your data allowance while there.

But O2 also offer their Travel Inclusive Zone on some of their more expensive deals. This gives you 120 mins, 120 texts and 150MB data every day while you’re abroad in these non-EU worldwide destinations.

Current O2 SIM only plans with extra roaming

Choose Travel Inclusive Zone as your O2 Extra when signing up to any of these:

If you get through that then you’ll actually get unlimited data, but with very limited speeds. For checking maps and browsing now and again, it’s a good scheme. It’s much better than paying these rates in any case.

Useful link: Our guide to the best roaming networks

✔ SMARTY are good for shorter trips to the EU

We appreciate networks that still offer EU roaming these days, as it’s becoming increasingly rare. It’s especially nice to see cheaper networks like SMARTY still offering it.

They do limit your data usage abroad to just 12GB a month. If you go over that you’ll have to pay for extra data. But that should be enough for most users and will only really affect heavy data users.

Annoyingly you’ll have to activate your SIM before you go abroad, otherwise you could get stuck abroad with no way to turn it on. This happened to us in testing, so make sure you turn it on first (see how to here).

But once you’ve got it working, SMARTY are a good network for going to the EU. Going further afield will get expensive as you’ll have to pay for your usage at these steep rates.

Useful link: SMARTY’s guide to their roaming

✔ SMARTY promise not to raise the cost of your plan

While lots of UK networks will increase the monthly cost of your plan while you’re on it to adjust with inflation, SMARTY have promised not to increase your monthly bill for the rest of 2023.

That’s great considering SMARTY are already a great value network as you’ll keep getting that great value for a long time. O2, on the other hand, raised their customers’ bills by 11.7% this year, which is huge.

SMARTY do offer some temporary promotions, such as 12 months at a discounted rate, after which your plan will return to its’ non-promotional cost. This can feel like a price rise. But on regular plans, your bill will stay the same.

Overall, SMARTY give you the assurance that you won’t have to end up paying more than you thought. Their prices may increase in 2024, but they will let you know beforehand and you can always leave if they do.

Useful link: Our network price increase guide

✔ No credit checks to pass or contracts to join on SMARTY

SMARTY aren’t just a cheaper alternative to Three, but also appeal to users who want the most flexible deal possible. SMARTY do this by making all of their plans pre-paid (where you pay up front for your allowance).

So when you join SMARTY you’re not joining on a contract. You just register a card and pay up front for your plan every month. You can set it to auto-renew or manually take out your plan each month.

That means you’re free to switch plans month-to-month if you’re paying too much or don’t have enough data. You can also leave SMARTY without giving notice by just not renewing your plan. It’s really that easy.

And finally there’s no way to accidentally run up a massive bill. That’s why SMARTY don’t need to check your credit history. So anyone can join SMARTY, even people with poor or no credit history.

Useful link: Why there’s no credit check on SMARTY

✔ Free entertainment trials on all O2 pay monthly plans

O2 are definitely a sort of “pay more to get more” network, where SMARTY are a low-frills, low-cost provider. Every O2 pay monthly plan gives you free trials to an entertainment service of your choosing.

These are O2 Extras and you can see your choices when taking out a pay monthly SIM only or phone contract in your basket. The current choices are Disney+, Amazon Prime, Amazon Music and more.

Qualifying SIM only plans with O2 Extras

Typically the more your plan costs the longer your trial (between 1 - 6 months). When your trial is over you’ll start paying for that service unless you manually cancel it, so don’t think of it as a freebie.

You can also take O2’s Travel Inclusive Zone benefit on their higher end plans. Overall, if you think you’ll make the most of these extras then they’re a nice addition to give you better value out of your plan.

Useful link: Full guide to O2 Extras

✔ O2’s Priority rewards app is a popular benefit

You don’t get any sort of rewards app on SMARTY. But O2 offer access to arguably the most popular rewards app, called O2 Priority, on any of their pay as you go or pay monthly plans. But what is Priority?

It’s a rewards app that is exclusive for O2 customers. In the app you’ll find special offers on high street and online shopping, food and drink as well as some freebies now and again.

Not only that, but you can also get priority tickets to specific events hosted at O2 sponsored arenas and venues. Experiences like rugby games, gigs and more are included. That will be an amazing benefit for some.

But bear in mind there’s a big difference in price between O2 and SMARTY. We recommend how much you’d actually get out of this kind of scheme and whether or not it’s worth the extra cost of O2’s plans.

Useful link: See current offers and events