You can find unlimited data SIM deals from nearly every major UK network now – but how do you decide which one is best?

We compare the deals and what you can expect from each network, along with expert advice on how to choose an unlimited data SIM.

UK networks with unlimited data SIMs

You can now get unlimited data from most UK networks:

BT Mobile (with BT Halo option selected) EE giffgaff iD Mobile O2 Superdrug Mobile Smarty Three Virgin Mobile Vodafone Voxi

Best unlimited data SIM-only deals right now

Below we’ve ranked providers by price and current deals. We’ve also flagged providers that have 5G connectivity:

														Was: £20 per month													

 															Now:  									£16 per month (£48 off)

You can often find the most competitive unlimited data SIM-O deals from Three. Its current promotion reduces the unlimited data plan rate to just £16 per month, outdoing its £17 per month Black Friday offer.

Pros: ✔5G-ready ✔Tethering ✔Global roaming ✔Go Binge

Cons: ✘ Go Binge available on cheaper non-unlimited plans

 															Now:  									From £22 per month (£11 first 6 months)

Pros: ✔50% off first 6 months ✔5G-ready ✔Entertainment plans include choice of streaming service for free  ✔Tethering ✔30-day terms available

Cons: ✘24-month contract ✘Speed restrictions on cheaper unlimited plans

														Was: £20 per month													

 															Now:  									£15 per month (for 12 months)

Smarty’s unlimited data plan normally comes at a palatable cost of £20 per month, and is now reduced to £15 per month for Christmas.

It’s not on contract, so you can stick to the package for as long or as little as you want. There are no speed restrictions either. Smarty operates off of Three’s network and you can use its tool to check your coverage.

You get up to 20GB at no additional cost if you’re abroad in the EU. There is a usage cap of 1000GB generally, which prevents commercial use of the SIM (which Smarty doesn’t allow).

Pros:  ✔Not on contract ✔No speed restrictions ✔Tethering ✔EU roaming ✔No credit check

Cons: ✘4G only ✘20GB data limit abroad 

 															Now:  									£20 per month

At £20 per month, it’s one of the cheapest unlimited data plans around. It’s not on contract so you can cancel any time. Plus, Superdrug points card holders can double their Health & Beautycard points when shopping. Superdrug also operates off Three’s network – you can check your coverage here.

Pros: ✔Not on contract ✔No credit check ✔Tethering ✔Includes EU roaming ✔Double Health & Beautycard points ✔£20 worth of Health & Beautycard points on joining 

Cons: ✘4G only 

														Was: £35 per month													

 															Now:  									£25 first month (£10 off the first month)

Lebera is the only provider that offers unlimited long distance minutes. See the full details of this plan.

														Was: £25 per month													

 															Now:  									£20 per month (£5 off per month)

iD Mobile, belonging to Carphone Warehouse, offers its unlimited data SIM-O plan on a 30-day rolling contract, which is great if you prefer flexibility. The SIMs also include EU roaming, so you can use your data at no additional cost while abroad. See iD mobile’s coverage

Pros: ✔Not on contract ✔Tethering ✔EU roaming 

Cons: ✘4G only ✘Credit check

 															Now:  									£30 per month (to BT Halo customers)

BT’s unlimited data plan is available for £30 per month if you are already on BT Halo unlimited highspeed broadband. It’s not the most cost-effective if all you’re after is an unlimited SIM, but might make sense to families already with BT at home, looking to upgrade.

Browse its other SIM-Only deals

Pros: ✔5G-ready ✔Tethering ✔Includes BT Sport ✔No capping in the UK ✔EU Roaming

Cons: ✘Available only to BT Halo customer ✘Capping at 50GB in EU ✘More expensive than other options

 															Now:  									£20 per month

GiffGaff operates off O2’s network and offers 4G connectivity – check your coverage. You can earn points when you refer other people to the service, which you can then convert into cash, credit or a donation to a charity.

Pros: ✔Tethering ✔No contracts ✔EU Roaming

Cons: ✘4G only ✘Caps at 80GB of data at high speed, then reduces to 38Mbps from 8am to midnight ✘20GB data limit abroad, 0.36p/MB charge thereafter

 															Now:  									£32 per month

Virgin Media offers unlimited data for £32 per month, but you have to be a TV or broadband customer. Check your coverage.

Pros: ✔ Tethering ✔Uncapped messaging on WhatsApp, Twitter and Facebook without eating data ✔No speed throttling (average download speeds are 37Mbps) ✔EU roaming

Cons: ✘4G only ✘12-month contract minimum ✘available only to existing broadband or phone users ✘13.75GB data limit abroad

 															Now:  									From £34 per month

EE’s unlimited data SIM-only plans start from £34 per month, which is again on the steeper side when networks like Three and Vodafone are in the £20-range. The speeds are up to 60Mbps though, which may justify it for some.

Pros: ✔EU Roaming ✔Tethering ✔Speeds up to 60Mbps ✔£60 worth of in-game extras in Harry Potter: Wizards Unite ✔Free Apple Music for 6 months ✔5G option available for £44 with Swappable Benefits 

Cons: ✘12-month contract ✘4G only 

 															Now:  									£35 per month (with Disney Plus free for 6 months)

O2 offers unlimited data SIM deals for 4G and 5G connectivity – and they’re both priced at £35 per month. Check your coverage with O2

Cons: ✘More expensive ✘15GB data capping abroad 

 															Now:  									£12 per month (with uncapped social media & video)

Grab 25GB of data for the price of 20GB along with Endless Social Media and Video (TikTok, YouTube, Prime Video and Netflix).

How do you use your data? First off, think of where you would use your data allowance the most. If you mostly stream video or music, or use social media, you may not necessarily need a totally unlimited plan.

Certain providers offer uncapped data on specific social media and streaming apps, so don’t fork out where you don’t need to! (On the topic of saving, there’s also this ridiculously good SIM-O offer with  60GB data for £8 per month)

For instance, Three’s  Go Binge feature allows unlimited use of Snapchat, Netflix, TVPlayer, Dave, Deezer, SoundCloud and Apple Music without eating into the data allowance – but you can get Go Binge on a plan as low as  £14 per month with 12GB data too. So unless you’re always on YouTube, you could effectively get away with unlimited data where it matters but on the cheap.

There’s also the Gamer’s Data Pass which allows unlimited access to Pokemon Go, Harry Potter: Wizards Unite, FIFA and Star Wars Galaxy of Heroes. It also covers uncapped live streaming from Twitch.

Not all plans are equal – Some plans have a speed caps on its unlimited plans. Vodafone for instance offers its unlimited plans on different speed tiers.

Vodafone’s  Unlimited Lite is its cheapest plan, at £22 per month but £11 the first 6 months, but you only get 2Mbps – which won’t be very handy if you often stream HD videos. Its standard Unlimited plan operates at 10Mbps maximum, while its Unlimited Max plan has  no speed restrictions.

Can you qualify for unlimited plans with your broadband provider? You may be eligible for an unlimited SIM through your broadband provider.

Virgin Mobile only offers it unlimited plan to its phone or broadband customers. Likewise,  BT only offers its unlimited data SIM to its Halo broadband customers.

Check your coverage. The last thing you want to be stuck with is a shoddy, slow connection. Most networks offer coverage checker tools on their sites (we’ve linked to them wherever possible in our chart above).

When is Black Friday 2020 – should you wait for a better deal?

Black Friday will take place on Friday 27 November, immediately followed by Cyber Monday on 30 November. Traditionally the biggest sales event of the year, it may yet throw up some even greater tech deals – but with so much uncertainty around finance and retail, and no guarantees regarding what discounts we will see, we advise you not to wait: if you see a deal you like, on a product you need, and you can afford the outlay, buy it today.

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Somrata researches and writes about the best tech deals to help readers make smart, informed buying decisions. She’s an expert on accessories and also reviews laptops, phones, audio and other devices.