Sky Mobile vs Three: compare their 4G/5G networks & benefits

✔ Sky typically offer more widespread 4G/3G/2G

Sky Mobile use O2’s network to provide signal to their customers, whereas Three use their own network. Both networks have advantages and disadvantages when it comes to signal coverage:

In terms of call signal (3G/2G) Sky have the upper hand. Sky’s signal also tends to be better at getting into buildings and you’re less likely to find yourself in a total blackspot in rural areas as they cover more of the UK’s total landmass.

We’d say Sky also win out for 4G coverage. But when you’re in larger towns and cities you’ll hardly notice a difference. The differences only become apparent in rural areas.

It’s always worth it to check each network's coverage using their official maps below to see which one has the better coverage in the areas you’re expecting to use your phone.

Useful link: More about Sky's network

✔ Three cover more locations for 5G

Three have devoted themselves to expanding their 5G network, more so than the rest of the UK networks. As a result you’ll be able to get 5G in more UK towns and cities than on Sky. And Three are by far the fastest network for 5G.

Three’s 5G is live in an impressive 300+ towns and cities, while Sky provide it in Sky have it in these 150+ locations. There is some overlap, but some areas are covered by one and not the other. But these numbers don’t tell the whole story.

Sky and Three's best 5G SIM only deals

Here’s what we think are either network’s best current deals that include 5G:

When a network claims to cover a town or city for 5G, you only actually get it in certain areas within those towns and cities (see street-by-street coverage). Networks tend to provide it in the busiest areas where 5G can best do its job.

Getting 5G is simpler on Three as you’ll get it automatically on all but their smallest plans. It’s free to get on Sky, but you have to fiddle around with your account settings. This shouldn’t be necessary as it’s already free.

Useful link: How to get 5G on Sky Mobile

✔ 4G on Three is typically faster than on Sky

When comparing networks on 4G speeds we look at the results from independent network testers Opensignal who measure typical speeds using millions of volunteer phones up and down the country.

They’ve consistently put Three above Sky’s hosts O2 in terms of 4G speeds for a while now (and we found little difference between Sky vs O2). Here's how they compare:

Three’s typical 4G speed results came out to 25.2 Mbps. On Sky’s hosts O2 the results averaged out to 17.1 Mbps (we’re certain speeds are the same on Sky and O2). But the speeds you get in real life will depend on where you are on both.

For your average browsing needs, checking emails and social media and so on, you’ll not likely notice a difference. But for more data-heavy activities, Three should be the better choice.

Useful link: What Three say about their network

✔ 5G speeds on Three are seriously fast

Three claim to have the fastest 5G network. To see if that’s true we looked at results from Speedtest by Ookla and Opensignal to see what sorts of speeds you can get on either networks’ 5G.

Between the two independent network testers you’ll see typical 5G speeds on Sky lie between 90.61 Mbps - 110.9 Mbps, compared to speeds between 103.9 and a blistering fast 248.16 Mbps on Three.

So Three’s claims are backed up by these results. On the flip side, Sky seem a bit underwhelming. But their 5G speeds will be more than enough for streaming HD videos and browsing.

But for the more data heavy activities like downloading large files, gaming or filesharing then the difference between either network could be noticeable. However, speeds will still vary per location.

Useful link: Our guide to the best 5G networks

✔ Three and Sky both offer WiFi calling

Networks offer WiFi calling as a feature to help eliminate indoor blackspots by letting your phone connect to calls using WiFi signal rather than conventional call signal (3G/2G). Both networks offer it on all plans at no extra cost.

As Three have offered if for longer they are able to offer it on more phone models (we found it also works with more phones than Three actually list here). You can also send/receive SMS messages via WiFi.

Sky Mobile don’t support as many phone models and you can’t send text messages over WiFi. And if you move from WiFi to 4G signal while on a call it will drop (Three will transfer your call over to 4G seamlessly).

It’s a double edged sword as Three have the better feature by far, but Sky’s call signal is better at getting indoors anyway so it’s not as necessary. Check your phone is covered in any case.

Useful link: 4G calling on Sky

✔ Both networks have free WiFi hotspot schemes

Three and Sky offer free WiFi hotspots, but only Three offer WiFi on Underground Stations. This is included on every Three plan, even on their cheapest ones.

Sky offer the Sky WiFi network of nationwide hotspots in popular areas like pubs and cafes. But they’re already free to access to there’s no exclusive benefit being a Sky Mobile customer for this.

Free WiFi hotspots are massively helpful for helping you keep your data usage down, especially if you’re on a smaller deal. And it can help to keep you connected in areas where mobile signal can’t reach.

It’s not a massive deal, however. Free WiFi is becoming more and more common in pubs, malls, restaurants and so on. WiFi hotspots aren’t the only way to stay connected on the go.

Useful link: Costs for going over your limit on Three

✔ Stream Sky’s TV apps without using up data

Sky Mobile offer a fantastic benefit for existing Sky TV customers that helps you get the most out of your mobile and TV packages:

Their Sky Watch benefit lets you stream every one of Sky’s TV apps (see full list here) without eating into your monthly data allowance so long as you’ve got Sky TV at home.

What’s even better is that it’s included on all of Sky’s plans (phone, tablet or SIM only) meaning you can take the very cheapest data plan and stream as much as you want with it:

However, there are a few things to bear in mind. Adverts that play while you’re streaming might come out of your allowance (this varies per app) and you’ll need some leftover data to benefit (50MB). But otherwise it’s a fantastic scheme.

Three used to have something similar for certain apps, called Go Binge, but they binned it a while ago. It’s a shame because it was a really good scheme, giving Sky an automatic win.

Useful link: What the Sky Go app can do

✖ Sky no longer include free EU roaming

More mobile networks have removed inclusive EU roaming from their plans and Sky Mobile are one of them. These days, using your phone in the EU comes with a fixed daily rate on Sky if you’re a new customer.

This is currently £2 for every day you’re in one of their EU destinations. There are no special passes or benefits to get around paying it, and that can add up to a lot if you’re on a long holiday.

You also won’t benefit from their free streaming while abroad. Any data you use to stream while there will come out of your allowance. Altogether that means there’s not a lot to love when it comes to Sky’s EU roaming.

But you can roam beyond the EU in their covered worldwide destinations at the same £2 daily rate. Compared to other networks that’s actually decent value, so that’s good news if you’re a worldwide traveller. Otherwise, Sky aren’t great.

Useful link: Full roaming costs per country on sky

✖ Three also don’t offer free EU roaming

Three sit at the bottom of our rankings for the best roaming networks for a reason. Their inclusive EU roaming scheme is long gone, so you now have to pay to roam in their EU destinations.

Long-term customers might still benefit from Three’s old roaming scheme if your contract isn’t up. But customers who joined not long before the 23rd of May and new customers will not get the benefit.

After that, you’ll have to pay £2 a day to unlock your regular UK allowance in the EU and £5 a day beyond the EU in certain destinations.

For EU roaming neither network is better or worse than the other, but going beyond the EU won’t put you out of pocket quite as much as on Three. It’s not a massive win, but Sky just take this category.

Useful link: Full roaming guide and all costs on Three

✔ Hold onto leftover data and gift it to other users

Sky have made it so you can avoid wasting unused data you've bought as part of your plan with their piggybank system - a sort of bank account for spare data you've not used.

Any data you didn’t get through at the end of each month will automatically go into your piggybank. That stays in there for you to withdraw any time you run out of data which you can do in 1GB increments.

If you've got multiple mobile deals on a single account, you can even send data to someone else if they run out. Or you can trade it for discounts off new devices.

It’s incredibly helpful for avoiding extra data charges if you run out. Sky let you keep unused data from one month for up to 3 years, so there’s no rush to get through or trade it in right away. Three offer nothing like this.

Useful link: Sky's full guide to their Piggybank system

✔ Three’s rewards scheme isn’t as impressive

Three introduced a new customer rewards app to replace their old Wuntu app a little while ago. They call it Three+ and they’ve been adding to it over time. Every Three customer gets access to the app.

The benefits usually include discounts or freebies such as special offers on restaurants, food delivery and cinema tickets. But this year they provided pre-sale tickets for the Reading and Leeds festivals.

Those sorts of big rewards don’t come around very often and you can’t choose which offers you want. So if the rewards you’re getting aren’t your cup of tea then this app won’t really do much for you.

Also, customers have reported issues with the app not working, not being able to log in or their offers not working in-store. It’s still a new scheme so we expect a few bugs. Three have an FAQs page if you have any issues.

Useful link: Three’s own guide to their Three+ scheme

✔ Sky’s phone contracts are very flexible

Sky’s phone contracts work by splitting the cost of your device and the cost of your airtime (mins, texts, data) plan into separate payments that are combined together to make your monthly bill.

You’re able to choose a 36-month deal (for a lower monthly cost spread out over a longer period) or a shorter 24-month one (paid off more quickly and cheaper overall).

And you can upgrade to a new model early or pay off what’s left of your loan once the first 12 months of your contract are up. You can even leave your airtime plan after this time without being charged cancellation fees.

We're not so keen on the Swap trade-in part of Sky's phone contracts, as you’re giving up the phone you’ve paid for. But what is nice is that you can use your saved up unused data to get discounts on your next upgrade.

Useful link: Use our phone deal comparison tool

✔ Three offer much simpler phone contracts

The best way to join Three on a phone contract would be through a re-seller like Fonehouse as they offer cheaper deals than joining via Three directly (compare deals using our comparison tool below).

In any case, all of their phone contracts are your standard 24-month ones, where your phone and usage are all part of the same contract payment (they’re inseparable).

They don’t offer the same degree of flexibility as Sky. You can’t choose your contract length nor do they let you upgrade early. But Three offer some genuinely good deals and the resellers offering Three contracts offer even cheaper ones.

Use our comparison tool here to compare all major networks directly and via re-sellers like Carphone Warehouse and more.

Useful link: Three's current phone range