Lyca Mobile
Lyca Mobile SIM Deal Uses EE's network

No contract

unlimited minutes

unlimited texts

Unlimited

data

£12.50

for 1 month

then £25.00

First month free
Free Roaming included
Smarty
Smarty SIM Deal Uses Three's network

1 month contract

unlimited minutes

unlimited texts

Unlimited

data

£15.00

a month

EU Roaming included
iD
iD SIM Deal Uses Three's network

1 month contract

unlimited minutes

unlimited texts

Unlimited

5G data

£15.00

a month

Black Friday
Data Rollover
Free roaming included
Talkmobile
Talkmobile SIM Deal Uses Vodafone's network

1 month contract

unlimited minutes

unlimited texts

Unlimited

5G data

£16.00

a month

EU Roaming included
Three
Three SIM Deal

24 month contract

unlimited minutes

unlimited texts

Unlimited

5G data

£20.00

a month

Three+ Rewards
O2
O2 SIM Deal

24 month contract

unlimited minutes

unlimited texts

Unlimited

5G data

£20.00

a month

EU Roaming included
O2 Priority
EE
EE SIM Deal

24 month contract

unlimited minutes

unlimited texts

Unlimited

5G data

£22.00

a month

Three
Three SIM Deal

12 month contract

unlimited minutes

unlimited texts

Unlimited

5G data

£23.00

a month

Three+ Rewards
Mobile networks may increase prices in line with the consumer price index each year. Please check individual network's terms before purchasing.

Which networks offer unlimited data SIM cards?

Three, Vodafone, O2, EE, Smarty Mobile, iD Mobile, VOXI, Lyca Mobile, Tesco Mobile, Asda Mobile, Talkmobile, Giffgaff and Lebara Mobile all offer SIM Only plans with truly unlimited data with no significant restrictions when used in the UK. 

Do I need an unlimited data SIM?

That depends on how much data you want to use. If you’re generally connected to Wi-Fi or don’t tend to stream video over your mobile network then you almost certainly don’t need unlimited data.

If on the other hand you like to stream Netflix during your commute for example then you might benefit from it.

To give you a better idea, here’s roughly what you can do with 1GB of data:

  • Stream standard definition video content for two hours
  • Stream 10 hours of high-quality music
  • Stream high definition video content for one hour
  • Download 150 songs
  • Upload 500 photos
  • Browse the web and social networks for 30 hours
  • Send 1 million instant messages
  • Play an online game for 3-30 hours (this varies a lot from game to game)

As you can see, most activities, including web browsing and music streaming, don’t use much data at all. The big data hits are video streaming and – in some cases – online gaming. If you’re downloading big files that will also give your data a major hit.

Can I use unlimited data abroad?

Not generally, but the exact amount you can use varies from network to network. For example, at the time of writing Three and Smarty let you use up to 12GB, O2 and Vodafone let you use up to 25GB, VOXI up to 20GB, EE up to 50GB, and Giffgaff, Talkmobile, and Asda offer up to 5GB. Lebara and iD Mobile meanwhile allow up to 30GB, while Lyca Mobile allows up to 35GB, though this varies from plan to plan.

At the time of writing, Tesco Mobile doesn’t advertise a limit on the amount of data you can use abroad, but in all cases these terms are subject to change, so it’s worth checking with the network direct for the most up to date information.

Can I use unlimited data for tethering?

Yes, outside of roaming restrictions (above) and general fair usage restrictions (below) you can use unlimited data for tethering on any of these networks.

Can I get a Data Only SIM with unlimited data?

Yes, Three, O2, Vodafone, and Smarty all offer unlimited data on a data-only SIM at the time of writing. Beyond that, a wide selection of networks offer Data Only SIM cards and many offer high allowances. It is also possible to buy an unlimited data SIM for a phone and put it inside a mobile broadband dongle, but you would lose out on being able to use the minutes and texts.

Are there any other restrictions?

This again will vary by network, but restrictions are typically minimal. In fact, Three, Vodafone, Asda Mobile, Talkmobile, iD Mobile, VOXI, Smarty, Tesco Mobile, and Lebara don’t advertise any general fair usage policy for data, while EE lets you use up to 600GB of data per month and tether up to 11 devices at once, O2 lets you use up to 650GB per month and tether up to 11 devices at once, and Lyca Mobile lets you use up to 450GB per month. On Vodafone meanwhile your speed will be restricted unless you opt for an ‘Unlimited Max’ plan.

Asda Mobile and Giffgaff also have speed restrictions on some plans, with the latter additionally having a 650GB monthly fair usage limit.

Other network restrictions are for the most part detailed above, but we’d always recommend checking with a network for the most up to date information.

What other benefits are there to being on these networks?

Aside from unlimited data plans there are a number of good things about many of the above networks.

Things to consider include roaming, for which some networks now charge or only offer it on more premium plans. However, O2, Smarty, iD Mobile, Tesco, Asda, Talkmobile, Lebara, Lyca Mobile, and Giffgaff have inclusive roaming as standard.

You should also consider what 5G coverage is like. This is something that is constantly changing as networks still have a lot of rolling out to do, but it’s worth using a network’s coverage checker before buying.

And you might want to look into other extras too. For example, on some Vodafone plans you can get an Amazon Prime, YouTube Premium or, Spotify Premium subscription included with your plan. EE similarly has a range of entertainment extras that you can choose from on select plans.

What SIM card size do I need?

That depends on your phone, but networks typically offer trio SIMs (sometimes called multi or combi SIMs) which means you’ll get a SIM card with all three SIM sizes (standard, micro and nano) in one. Then you just pop out the size that fits your handset.

Generally newer handsets use the smallest size (nano), while older ones may use a micro SIM card. You probably won’t need a standard SIM card unless your phone is very old. Find out more.

Do I have to stick with my current network?

No, if you’re out of contract you can switch to any network.

Text ‘INFO’ to 85075 or give your current network a call if you’re not sure whether you’re out of contract or not.

How do I keep my number?

Keeping your number is easy. Once you’ve ordered your new unlimited data SIM Only deal just text 'PAC' (from your old number) to 65075 or ask your current network for your PAC code, then give it to the network you’re joining.

If you do this within 30 days of the PAC code being issued then your number will be ported, and this usually happens within the next working day. Find out more.

Will I lose service if switching network?

Yes, if you’re porting your number, but only for a very short amount of time while the transfer is actually happening (usually a matter of hours at most and often only seconds).

Can I switch from a Pay Monthly phone contract to an unlimited data SIM Only contract?

Yes, simply make sure you’re out of contract, then order the new unlimited data SIM Only deal and – if you’re also changing network - inform your old network that you’re leaving.

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