Sky Mobile vs O2: key differences between the networks

✔ Coverage is identical on Sky and O2

While Sky isn’t owned by O2, they do use O2’s network for calling and data signal. They signed a long-term deal to use them in future too, so this isn’t something that will change anytime soon.

You get identical 4G signal on Sky as you would on O2. They are a bit behind some networks for 4G data but you’ll get it basically everywhere in populated areas and in some surprisingly rural areas.

And you’ll get 5G in the same long list of 3200+ UK towns and cities on Sky as O2. Coverage within these locations is generally very good, so you’ve got a good chance of staying connected as you move around too.

Best 5G SIM only plans on Sky and O2

Finally, you get identical 2G/3G call signal on Sky and O2 as well. While O2 are slowly removing this to expand their 4G, they currently have the best network for calls so it’s good you get full access to it on Sky.

Useful link: Which network has the best indoor signal?

✔ Data speeds are the same on both providers

While some Sky users question if Sky Mobile offer the same 4G speeds as being on O2 directly, we’ve never found any evidence of a speed cap or differences in speeds when we’ve tested them ourselves head-to-head.

Our tests showed identical speeds on both, going as high as 90 Mbps in the city, while they went down to 5 Mbps in the country. More often we sat around 20 Mbps, lining up with Opensignal’s result of 23.1 Mbps.

That applies to 5G as well, with identical typical speeds of 80.1 Mbps according to Opensignal and 83.02 Mbps according to Speedtest. Expect peaks around 226.14 Mbps from Speedtest’s report.

While it’s good that speeds are identical, it puts them both in the unfortunate position of being the slowest network for 4G and 5G speeds. Still, you won’t get an inferior experience on Sky vs being on O2.

Useful link: See Sky’s full range of 5G SIM only plans

✔ Extra network features are a bit better on O2

Considering that 2G and 3G will be removed in the future, it’s crucial for both providers to include WiFi/4G calling so customers can continue to make calls. Thankfully, both of them offer it on all plans.

Both have identical features in terms of how they work, letting you send/receive texts and transfer calls from WiFi to 4G without them dropping. But O2 support more devices, making it easier to get it working.

Best WiFi calling plans on Sky and O2

O2 also offer a large network of 15,000+ free WiFi hotspots with some on the London Underground. Sky also have a lot of free WiFi hotspots, but anyone can join these so it’s not a unique benefit of joining Sky.

Sky now let you join on an eSIM like on O2. It’s a slick scheme on both, so there’s not much to split them on there. And Sky impressively offer visual voicemail and call forwarding, just like O2.

Useful link: O2's guide to all their network features

✔ Inclusive EU roaming only comes on O2 between them

Like many other providers, Sky removed their inclusive EU roaming a while ago. O2, on the other hand, have kept theirs in place. Now only O2 let you roam in the EU at no added cost between the two.

On Sky you have to pay £2 a day to roam in all of Sky’s covered EU destinations. There are no ways around this and it can add up if you’re on a long trip. But at least your data allowance isn’t limited while there.

O2 let you roam in these 48 EU countries at no extra cost on all their plans. They’re the only main network to offer this and they let you use up to 25GB while you’re there, which is a pretty flexible amount.

Best SIM only deals on O2 and Sky Mobile

But Sky are a decent option for going beyond the EU as their £2 daily rate applies to lots of worldwide countries too. That’s pretty good and can be cheaper than paying for a Travel Inclusive Zone benefit on O2.

Useful link: Sky's full guide to roaming on their network

✔ Get Priority rewards and more on O2

The main thing you get on O2 that you don’t on Sky is access to O2’s Priority rewards app. This gives you special offers on high street food, drink and shopping that can save you a handy bit of money here and there.

You can also get access to presale tickets for concerts and gigs hosted at O2 sponsored gigs, which can be amazing depending on what you want to see. It’s one of O2’s best unique benefits.

Best current SIM only deals on O2

O2 also give you 20% off any extra plans you add to your account. So you can get a lot of money off if you need to get your whole family on their own plans, which helps make up for O2’s generally higher prices.

Lastly, O2 let you take a free trial to Disney+, Amazon Prime, Amazon Music Unlimited or Audible with the length of your trial depending on the cost of your plan. Sky strangely don’t offer anything like this.

Useful link: Read more about O2’s Priority app

✔ Get excellent data rollover and more on Sky

Sky offer their data rollover benefit on all their plans. This puts any unused data at the end of the month into a “piggybank” which you can withdraw from at any point. And this data lasts for up to 3 years!

They go a step further by letting you gift this rolled over data with other users on your account. That’s a great way of preventing your kids from going over their allowance and racking up a huge bill.

Sky also let you stream their TV apps without eating into your data allowance. That’s brilliant if you’re a Sky TV customer and lets you keep up with your favourite shows without worrying about your data usage.

Best current SIM only deals on Sky

Lastly, Sky offer more flexibility on their plans, letting you switch to a bigger or smaller plan each month. And you can set a spending cap between £0-£100 in £1 increments, which is more flexible than O2’s caps.

Useful link: Sky's help article about data rollover

✔ O2 are more flexible, Sky are generally better value

Both O2 and Sky offer phone contracts based on split finance agreements (basically loans) where the payment for your phone and usage plan (mins, texts and data) are billed separately. This has some nice upsides.

This kind of contract lets you pay lump sums to reduce your monthly bill or pay off the cost of your phone whenever if you want to upgrade early. But O2 offer even more flexibility with their “Custom Plans”.

These let you set a contract length between 3 and 36 months to suit your budget, while Sky only let you choose 12 or 24 months. But the price of your phone will stay the same no matter what on both.

But you have to stay on your O2 usage plan for the full 24 months. And O2 are more expensive both on the cost of their phones and usage plans, so Sky will be a better choice if you’re looking for sheer value.

Useful link: Read O2's guide to their Custom Plans