BT, Sky, Tesco and Virgin – a genuine alternative to the 'big 4' mobile networks?

MVNOs can be a great way to get a cheap mobile phone deals

Analysis paralysis is a fantastic expression. Not only does it rhyme (which we love), but it concisely sums up that freezing feeling you get when faced with more options than you can possibly process. Netflix series. Soup flavours. Short-break destinations. Sometimes a wealth of choice can be counterproductive.

For better or for worse, choosing your mobile phone network hasn't been quite so paralysis-inducing over the last few years, as four networks have dominated the scene: EE, O2, Vodafone and Three. They each have their perks (O2 Priority rewards, EE's fast 4G speeds) and specialities (Three mobile deals run the roost on big data tariffs), but generally it's a race to the bottom to offer the most competitive prices on the flagship phones.

But the growth of Mobile Virtual Network Operators (MVNOs) means other companies are now able to break up the monopoly more effectively, by piggybacking off the coverage of the bigger networks. And these are no obscure names either: BT Mobile, Sky Mobile, Tesco Mobile and Virgin Mobile have come to the forefront of the MVNO scene, each with some interesting propositions. Good for your bank balance, bad for analysis paralysis.

The Big Deal is here to tell you more about the biggest names in MVNO, and whether it makes sense for you to move away from the big four operators.

BT Mobile

Not so long ago BT was the first company one thought of in respect to telecommunications in the UK, and it was at the forefront of the blossoming mobile phone industry in the 1990s under the BT Cellnet sub-brand. This became O2 just after the turn of the millennium, and BT sold the concern to Telefónica a few years afterwards. But BT Mobile came back to the market in 2015 when... actually, that's probably enough of the history lesson.

What you need to know is that BT Mobile becomes worth a look if you already have your internet plan with BT Broadband. If you do, then you can claim £5 per month off your mobile phone tariff. It still doesn't compete too well on big flagship phones like the iPhone X or Galaxy S9, but broadband customers can enjoy some of the best iPhone 7 and iPhone SE deals around.

If you already have your internet plan with BT Broadband, you can claim £5 per month off your mobile phone tariff.

SIM only deals on BT also become much more attractive if you're already an internet customer, as the fiver off still applies – and the company has a generous and ongoing reward card promotion that makes it one of the cheapest places to get your SIM card from.

Okay, so here's a little bit more history to end on (next week: Tudors and Stuarts). BT bought out EE in 2016. That means BT naturally has the benefit of using EE's rapid 4G coverage, although you don't get the free Apple Music or BT Sport subscriptions you'd get with a direct EE phone deal.

Discover BT's best mobile phone deals

Sky Mobile

With its big fat fingers already in the flavoursome television and broadband pies, it's no surprise that Sky wanted a slice of mobile as well. And it's an experiment that has earned it plenty of praise, including the Best Value Network prize at last year's Mobile Choice Consumer Awards.

Sky Mobile got that gong for the choice and flexibility of its mobile phone deals, allowing you to cut costs for things you don't need. Not bothered about making calls or texts from your mobile? Then save £10 per month by removing them from your plan. Got no intention of upgrading your phone for a couple of years? Then go for a Swap 24 tariff for the best prices.

Sky Mobile has earned plenty of praise, including the Best Value Network award at last year's Mobile Choice Consumer Awards

You won't find any Huaweis, HTCs or Honors at Sky (is there such a thing as being H-ist?); it only stocks the biggest phones from Apple, Samsung and Sony. But the slim pickings and saving opportunities mean that it can offer some rock-bottom prices, like its untouchable 10GB for £41pm iPhone X deal.

If you're the kind of person who hates waste Sky Mobile offers data rollover, so you can carry any unused data from a month on to the next – none of the big four offers the same. And it's worth noting that in the last few months Sky has been able to offer better and better free gifts with certain mobile phone deals – just last month we were gobsmacked by the PS4 plus Gran Turismo they were giving away with Sony smartphones.

Head to the Sky Mobile to find out more

Tesco Mobile

Like the supermarket itself, Tesco Mobile's main selling point is value. And we've seen it come up with some terrific tariffs, particularly on some of the best budget phones on the market. It really comes into its own when catering to the same kind of people who prowl Tesco store aisles looking for bargains.

And Tesco Mobile has a couple of tricks up its sleeve to really ring as much value as possible from your mobile plan – every little helps, we hear. For example, with the Tesco Xtras app you can shave £3 per month off your bill – the only downside is that you'll be bombarded with Tesco adverts every time you unlock your phone.

Tesco has a couple of tricks up its sleeve to really ring as much value as possible from your mobile plan – every little helps, we hear

Tesco Mobile reserves its best prices for 30-month contracts, which is half a year more than the likes of EE, Vodafone, and O2 (on whose coverage it piggybacks) require. If that makes you run a mile, then we absolutely understand. But the rapid growth of the SIMO market over the last few years suggests that people are happier to hang on to their mobiles for longer these days, slotting in a cheap SIM when their contract ends. So for the money you'll save, a 30-month contract probably isn't so bad.

Unlike some other MVNOs (cough Sky Mobile cough), Tesco has a wide and varied choice of handsets. Cheaper, more unfashionable brands such as Alcatel and Doro line up alongside the iPhones and Samsung Galaxys of this world.

See what mobile phone deals Tesco Mobile has to offer

Virgin Mobile

Virgin Mobile always gets our attention when a new flagship phone launches. Take the new Galaxy S9 as the perfect case study. When all the likes of O2 and EE could manage was more than £40 per month after a big spend upfront, we noticed that Virgin was able to offer it for £31 per month, and with absolutely nothing upfront. You can see why our interest was greatly piqued.

"What's the catch?" we hear you ask. Well of course there is one: to get that ridiculously low monthly price you have to sign up to a three-year contract. Thirty-six whole months of cradling your phone like a babe in arms, not to be as much as scratched – let alone left in a taxi or smashed to smithereens.

That's pretty much par for the course on Virgin – the cheapest mobile phone deals but on the longest contracts

And that's pretty much par for the course on Virgin: the cheapest mobile phone deals but on the longest contracts. As advancements in technology plateau even more, chopping and changing your phone every couple of years does now seem to be less and less necessary. So if you really want a bargain – and you've chosen your handset carefully from our best phone buying guide – then it may be worth losing your cherry to Virgin.

As you'd probably expect from Virgin, its mobile strand has a few gimmicks going to attract you its way as well. Like Sky, you can roll your unused data over to the following month. And, social butterflies that we are, we really like the way that using WhatsApp, Facebook Messenger and Twitter away from Wi-Fi doesn't use up any of your precious data allowance. Nice touch.

Discover Virgin Mobile's best mobile phone deals

So should I go with an MVNO?

It's brass tacks time, isn't it? Well, the fact that 55% of people who changed their network last year went to an MVNO means it probably doesn't matter what The Big Deal thinks. And that's okay. Honestly.

But if you do want our opinion (and we're going to give it to you regardless), then it can really pay dividends to go with an MVNO. The money to be saved, and the extra perks they offer over the usual operators, make them an increasingly attractive option.

Yes, you'll have to compromise. MVNOs don't yet offer the sheer choice of smartphones that the big four do, and you'll be frozen out from the best prices from the likes of BT and Sky unless you have other services with them. You may end up on a longer contract than you'd usually go for, too.

But if you have no particular loyalty to a network, and just want to pay as little as possible, then be sure to check out an MVNO before you commit to the quotidian quartet.

If you want to discuss, debate or deliberate any phone deals news and views, then head over to our @TRDeals twitter feed – you'll also find the latest offers on phones, TVs, consoles, broadband and more tech.