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Sky Mobile vs BT Mobile review: UK mobile providers compared

Looking to go mobile with the broadband, phone and TV giants? We tell you which is best

Sky and BT both want the same thing: to sign you up for a quartet of services, including broadband, home phone, TV and mobile. Both will sell you a phone or a SIM-only plan whether or not you’re an existing customer, but both offer their best deals to current subscribers – or to those prepared to make the switch.

The two offer very similar services, but both Sky Mobile and BT Mobile have their own distinctive style and features. Which should you go for, and does it all depend on where you have your existing TV and/or broadband deals? To find out, here’s a comparison of the two Mobile Virtual Network Operators (MVNO) to help you make the right choice.

Sky Mobile vs BT Mobile review: Contract length and roll-over

One of the main reasons to consider Sky Mobile over other networks is its ‘Piggybank’ data rollover; any extra data you have remaining from the previous month will be added to this month’s allocation, so you get another chance to use the data that you’ve paid for – or you can cash in unused data for a range of other rewards, including money off devices and accessories in Sky’s own Sky shop. There are some limitations – your unused data enters the Piggybank at the end of every month and you can only roll it back into the next month in 1GB to 5GB batches – but otherwise it’s a very flexible system. Your Piggybank can store data for up to three years.

O2, Virgin Media and iD Mobile all offer similar rollover features, but Sky’s keeps your allowance for longer, rather than wiping the slate clean every month to hold back just the last month’s allowance. Sky’s Piggybank even works with multi-SIM contracts (you can have up to five on a single account), with each SIM adding to the same data pot. If one of you doesn’t use much data but another is a real data hog, you can use the Piggybank to share the allowance around.

READ NEXT: Our pick of the very best mobile networks

This isn’t the only example of Sky’s flexibility. Because Sky separates your phone payments from your plan payments (if you have a phone), you’re free to change your data plan at any point with just thirty days notice. You can also switch from the £10 calls and texts plan (free if you’re a Sky TV subscriber) to a Pay as You Use option. If you don’t use your phone for calls and texts you can save up to £10 a month. What’s more, Sky’s rollover carries on working when you increase or decrease your data allowance. Take out a 5GB plan for a couple of months, then switch to a 2GB plan, and you could still have 6GB or more sitting in the Piggybank waiting to be used.

As far as we’re aware, no other UK provider gives you this level of freedom within a fixed-term contract – and BT definitely doesn’t. Its all-in contracts don’t allow you to switch up and down so easily. However, if you’ve taken out the firm’s family SIM contract, you can add or remove family members from your primary 12-month contract package with 30-days’ notice and not have to worry about any penalty charges.

Winner: Sky Mobile

Sky Mobile vs BT Mobile review: Price and package deals

Both Sky and BT Mobile sit in the mid-range of the mobile network market, above the no-frills options but below the big-data, high-performance players. Here, pricing is absolutely crucial, and both have some strong SIM-only deals.

Sky Mobile keeps things simple with four different packages giving you 1GB for £6, 2GB for £12, 8GB for £15 and 15GB for £20. Remember that calls and texts aren’t necessarily included; they’re free for Sky TV customers, but £10 a month on top if you want Unlimited Calls or Texts – and pretty pricey at 10p per minute and 10p per text on Pay as You Use. Sky also now sells tablets with the same mobile plans, giving you mobile data with an iPad, iPad Pro or Galaxy Tab if you’d rather use a slate than a smartphone.

Data only (Non-Sky TV customers)Data + unltd mins/text (Non-Sky TV customers)Data + unltd mins/text (Sky TV customers)
1GB£6/month£16/month£6/month
2GB£12/month£22/month£12/month
8GB£15/month£25/month£15/month
15GB£20/month£30/month£20/month

(Above: Sky Mobile’s mobile plans)

Where BT has its family plans (see below), Sky allows you to have up to five contracts attached to the same household account, but with no actual discount involved. You can share unused data in the Piggybank, but that’s as good as it gets.

Predictably, Sky surges ahead on integrated TV services. Sky Mobile now includes Sky Go Extra, allowing you to download movies and programmes to your phone or tablet for watching later.

BT can’t match Sky Mobile for eye-catching gimmicks, but it has a wider choice of plans, ranging from the £13/500MB Great Starter Plan through the £15/2GB Casual Usage plan to the £40/30GB Max Plan. Its plans seem a little more expensive than Sky’s for a given allowance, but BT includes calls and texts where Sky only gives you data (without a Sky TV account). What’s more, BT customers get a £5 discount on each plan, bringing the price down further.

Great Value Starter Plan

The Casual Usage Plan

The Essential Plan

The Savvy Saver Plan

Price

£13/month (£8/month for BT Broadband customers)

£15/month (£10/month for BT Broadband customers

£17/month (£12/month for BT Broadband customers

£18/month (£13/month for BT Broadband customers)

Data

500MB

1GB

3GB

6GB

Minutes

Unlimited

Unlimited

Unlimited

Unlimited

Texts

Unlimited

Unlimited

Unlimited

Unlimited

Wi-Fi

Unlimited

Unlimited

Unlimited

Unlimited


The Perfect All-Rounder Plans

The High Data Plan

The Ultimate SIM Plan

The Max Plan

Price

£20/month (£15/month for BT Broadband customers)

£23/month (£18 for BT Broadband customers)

£25/month (£20 for BT Broadband customers)

£35/month (£30 for BT Broadband customers)

Data

12GB

10GB

20GB

40GB

Minutes

Unlimited

Unlimited

Unlimited

Unlimited

Texts

Unlimited

Unlimited

Unlimited

Unlimited

Wi-Fi

Unlimited

Unlimited

Unlimited

Unlimited

(Above: BT Mobile’s mobile plans)

And if you want further savings, BT Mobile also has a family SIM feature. Take more than one SIM under the same contract (from the Casual Usage Plan upwards) and the price per-sim drops as the number of SIMs increases. Sign up for the High Data Plan with three SIMs, for example, and you’d pay £41.40 per month all-in or £13.80 per SIM; a saving of over £27 on the three SIMs paid for separately.

It’s hard to make direct comparisons between the two services, but if you aren’t a customer of either then BT offers more bang per buck. You could have BT’s 10 or 12GB plans for less than the cost of Sky’s 8GB plans, once you factor in the extra cost of texts and calls.

Winner: BT Mobile

READ NEXT: The best pay-as-you-go SIM deals for value, roaming, data and more

Sky Mobile vs BT Mobile review: Coverage

Both Sky and BT are mobile virtual network operators (MVNO), which means they use another operator’s infrastructure to deliver your voice calls, texts and data.

BT Mobile uses EE’s network, which is also owned by BT Group. By utilising EE’s network, BT Mobile customers have close to flawless 4G, 3G and 2G coverage. At 99%, 98% and 99% population coverage respectively, BT boasts wide UK coverage.

(Above: BT Mobile’s network coverage)

Sky, on the other hand, makes use of the O2 mobile network, which used to be distinctly second-best. However, O2 has invested in network improvements over the last few years, purchasing new bandwidth and installing new infrastructure. As a result, UK coverage by population now stands at 99% across 4G, 3G and 2G, though independent checks by RootMetrics in the first-half of 2018 put O2 behind EE (and Vodafone and Three) for 4G coverage by geography. Issues with data connectivity in early December 2018 haven’t helped O2’s case, though the expectation is that these were only temporary.

(Above: Sky Mobile’s network coverage)

This one’s a close one, and Sky wins on O2’s figures, but BT Mobile is winning in RootMetric’s tests. Before you sign up to a network, it’s always worth talking to any friends who use that network to find out how it works for them. You can even trial a PAYG SIM for a week to see how coverage and performance holds up where you live.

Winner: Tie

Sky Mobile vs BT Mobile review: Roaming charges

Whether you’re a frequent traveller or like using your phone for info while on holiday, roaming provisions are essential. Things are easier since the EU scrapped roaming charges within its borders (though what happens post-Brexit remains to be seen). As a result, both BT and Sky let you use your data, calls and text allowances within the EU and EEA at no extra cost. BT goes a little further, covering 47 destinations in its Roam Like Home tariff where Sky only covers 30 in its Roaming Passport. However, BT can get very expensive outside those 47 countries, while Sky is a little cheaper and has a Roaming Passport Plus option, where you pay £5 a day to use your allowances in ten further countries including Australia and the US. On balance, we’re going to call this one another draw.

Winner: Tie

Sky Mobile vs BT Mobile review: Verdict

The two network providers have good deals on mobile contracts. Both have their pros and cons, but if you forced us to choose a new contract from one of the two operators, we’d lean toward BT Mobile as it offers cheaper contracts and better performance while matching Sky elsewhere. Its family-friendly features also shouldn’t be underrated. However, Sky Mobile offers the most flexible package and gives you the ability to roll over data, which is a very handy feature for peak data-usage months.

Our verdict changes if you’re a current Sky TV or BT Broadband customer. The benefits of being with either BT or Sky will impact the overall price you pay for your mobile contract, saving you £10 if you’re a Sky customer (and opt for Sky Mobile) and £5 if you’re a BT customer (and opt for BT Mobile). This makes each package more appealing.

If you’re a current Sky TV customer, get Sky Mobile. If you’re a current BT Broadband customer, get BT Mobile. If you aren’t a customer of either, get BT Mobile – or check out our current rundown of the UK’s Best Mobile Networks and look elsewhere.