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Compare SIM only deals: pay monthly plans on every network

Compare SIM only plans

The retailers featured on this page may compensate us when our readers follow links to their websites and make a purchase. More

Use our price comparison tool to find the best SIM only plan for the minutes, texts and data you need and monthly budget.

Compare all SIM only plans

Find a SIM only plan

Choose what you want from your deal

SIM card and magnifier

Networks

Providers:

1p Mobile logo
Three logo
ASDA logo
Boshhh Mobile logo
Coop Mobile logo
EE logo
giffgaff logo
Honest logo
ID logo
IQ logo
Lebara logo
Lycamobile logo
O2 logo
SMARTY logo
Sky logo
spusu logo
Talkhome logo
Talkmobile logo
Tesco logo
Vodafone logo
VOXI logo

Plan

Data: (0MB+)

Minutes: (0+)

Contract

Maximum length: (Any)

Added features

Best SIM only deals in March

Overall strongest deals

iD Mobile SIM only deal
SIM only
just
£6
a month
🛈 No annual price rises

Unlimited mins and 8GB data See full deal

at idmobile.co.uk
(opens in new window)

Every month, we pick out 3x standout plans for price that are good for a small, medium and heavy mobile user. For March, here's our winner for out-and-out cheapness:

For someone that needs a medium amount of data:

Or for anyone that needs absolutely loads of data:

Vodafone logo

Unlimited minutes + Unlimited texts + 0MB 120GB data (5G) = £0 £14 a month (12‑month contract)
£50 Currys gift card (automatic, no need to claim)
See full deal

🛈 Monthly price + out of bundle charges will increase every April by the Consumer Price Index rate of inflation + 3.9%

The main networks' best SIM only deals

Three SIM only deal
SIM only
just
£7
a month
🛈 Monthly price will increase each April by the Consumer Price Index rate of inflation published in December + 3.9%

Unlimited mins and 8GB data See full deal

at three.co.uk
(opens in new window)

If you want to join one of the main UK mobile networks (EE, O2, Three or Vodafone) this March, here's the best deal on each:

Three logo

Unlimited minutes + Unlimited texts + 0MB 8GB data (5G) = £0 £7 a month (12‑month contract)
See full deal

🛈 Monthly price will increase each April by the Consumer Price Index rate of inflation published in December + 3.9%
Vodafone logo

Unlimited minutes + Unlimited texts + 0MB 30GB data (5G) = £0 £10 a month (12‑month contract)
£25 Currys gift card (automatic, no need to claim)
See full deal

🛈 Monthly price + out of bundle charges will increase every April by the Consumer Price Index rate of inflation + 3.9%
O2 logo

Unlimited minutes + Unlimited texts + 0MB 150GB data (5G) = £0 £0 a month for 3 months, then £23.99 (24‑month contract)
See full deal

🛈 Monthly price will increase each April by the Retail Price Index rate of inflation published in February + 3.9%

Cheapest SIM only deals

spusu SIM only deal
SIM only
just
£2.90
a month
🛈 No price rises in 2024

Unlimited mins and 1GB data See full deal

at spusu.co.uk
(opens in new window)

Unlimited data SIMs

SMARTY SIM only deal
SIM only
just
£16
a month
🛈 No annual price rises

Unlimited mins and unlimited data See full deal

at smarty.co.uk
(opens in new window)

100GB data or more

Talkmobile SIM only deal
SIM only
just
£11.95
a month
🛈 No price rises in 2024

Unlimited mins and 120GB data See full deal

at talkmobile.co.uk
(opens in new window)

30GB data or more

iD Mobile SIM only deal
SIM only
just
£7
a month
🛈 No annual price rises

Unlimited mins and 30GB data See full deal

at idmobile.co.uk
(opens in new window)

10GB data or more

Talkmobile SIM only deal
SIM only
just
£11.95
a month
🛈 No price rises in 2024

Unlimited mins and 120GB data See full deal

at talkmobile.co.uk
(opens in new window)

4GB data or more

Lycamobile SIM only deal
SIM only
just
£4
a month
🛈 No price rise guaranteed until 2026

Unlimited mins and 5GB data See full deal

at lycamobile.co.uk
(opens in new window)

Tips on choosing and switching to SIM only

1. Find out if your current contract is actually over

Screenshot of O2 contract end date

Check your contract is ending

Before switching over to a new network, you’ll have to make sure your current SIM only or phone contract is actually finished, or at least close enough to finishing for you to switch.

You might be liable to pay early termination charges if there’s anything more than a month left on your current deal, so switching could cost you more than it’s worth.

To see how close you are to finishing your contract text “INFO” to 85075. This works the same way for every provider. What then happens is you’ll receive a text from your provider telling you how much you’d be liable to pay for cancelling.

If you’re on pay as you go, you don’t need to do any of this. You’re always free to leave whenever you like, you’ll just need to stop topping up or buying your monthly bundle. And that’s it.

2. Think about what sort of usage you need

Screenshot of Virgin Mobile app

Check how much data you already use

Before you go off to search for a new plan, you should know exactly what you’re looking for. We recommend checking your current usage plan, seeing how much you actually use and think about how much you want.

This is essential. When you start comparing, networks will try and lure you in with massive data plans that you might not even need. You wouldn’t go to a restaurant and order a steak 8x bigger than you can eat.

Many networks provide an app to help you keep track of the data you use in an app or online account. Have a look, but if there’s no way of checking then you should call your provider and ask. Your phone might track your usage.

The majority of deals now have unlimited minutes and texts, so data is the main thing to think about. If you currently restrict your data usage to avoid extra charges, think about adding some headroom in your next deal.

Useful link: Use Tesco Mobile's data calculator

3. Look at what you’re currently paying

EE bill screenshot

Check plan cost and extra costs

Your task here is to find out what you’re spending on average per month. Not just what your headline monthly plan cost is. But whether you’re racking up extra charges on going over any limits regularly.

Like with your usage, you should be able to find a breakdown of your billing information on your provider’s app or in your account settings. Calculate how much you’re spending a month and keep it in mind.

It’s really common that people plump for a deal at a certain cost because it appealed at the time. And then end up constantly paying more than that amount, because the plan wasn’t actually suitable for their needs.

The best thing to do is to find a SIM deal that suits your monthly needs, not just a super cheap deal that is too small. That will have you going over your allowance and being stung by extra charges.

4. See if your phone is still locked to a certain provider

Phone and an unlocked padlock

Some networks still lock phones to them

Ofcom got a new law introduced on the 17 December 2021 making it illegal for mobile networks to sell phones that are locked to their network, meaning that no other SIM would work except one from them.

If you bought your phone before the law was passed then you’ll have to contact your network to get your phone unlocked. If you didn’t buy your phone directly from them you’ll have to get this done, which could cost you money.

Either just ring your mobile network if you’re currently in a phone contract with them. Or if you know someone with a SIM card from another provider, put it in the phone and make sure connects to that network fine.

Make sure you do this before you switch, as getting a brand new SIM only to find out it doesn’t work can be infuriating. In any case, it shouldn’t be too much of an issue in the future.

5. See which mobile network suits you best

Mobile mast and a ratings hand

We've reviewed every major networkRead network reviews

at simsherpa.com
(opens in new window)

In the UK, there are only actually four mobile network operators that own and maintain the physical infrastructure that delivers mobile signal to your phone. These are EE, O2, Three and Vodafone.

But you may or may not know that there are many other networks called “virtual operators” who are so called because they piggyback off the major networks to give their customers signal. They also tend to be cheaper.

So we first recommend checking your local coverage with each main networks. Use EE’s checker here, O2’s here, Vodafone’s here and Three’s here. Don’t just check at home, look anywhere you’ll conceivably take your phone.

Once you know which networks best cover your area that should narrow down your choice for which one you will go through. In the dropdown below we list all the main networks and which providers use them.

EE

BT Mobile, EE, Plusnet Mobile*, IQ Mobile, Virgin Mobile*
* coverage not 100% identical so check before you buy

O2

giffgaff, Lycamobile, O2, Sky Mobile, Tesco Mobile

Three

Honest Mobile, iD Mobile, SMARTY, Superdrug, Three

Vodafone

Lebara, Talkmobile, Virgin Mobile, Vodafone, VOXI

6. Consider which network features you need

WiFi calling icon

Features like WiFi callingRead our guide

at simsherpa.com
(opens in new window)

You might find yourself struggling to get call signal in your home. If so, you’ll want to make sure you go with a network that offers WiFi calling. This lets your phone connect to calls using WiFi instead of call signal.

Most virtual operators offer it now, but not all of them. So read our WiFi calling guide here for the full list. If it’s something you think you’ll need, it will help you rule particular networks in or out of your shortlist when you compare.

The other major network feature to think about is 5G. If you’re an expert data user or just like having the latest thing, have a read of our guide to the mobile networks with 5G to narrow down your shortlist.

Basically, this step is just about making sure you get what you need out of your deal, rather than just going for a cheap deal and then having to change it because you’re not satisfied with it.

7. Compare prices on SIM only deals

Use all the requirements you’ve found above to filter these plans

A SIM card and a magnifying glassUse our tool here

8. Bring over your old number onto your new network

Ofcom text to switch explanation

Keep your number with a textHow it works

at simsherpa.com
(opens in new window)

Once you’ve settled on a new SIM deal all you’ll need to do before buying is to tell your old network that you’re leaving. These days you can do this without having to talk with them. Here’s how:

With your old mobile SIM in your phone, text PAC to 65075. They’ll send you a code to give to your new provider, which instructs them to end your current deal and transfer your mobile number across.

You can give this PAC to your new network either at the checkout when taking your new SIM or once it has been delivered. We’d recommend waiting until your SIM has been delivered just in case.

If you’re not fussed about keeping your number, you text STAC 75075 instead. Give that to your new network and they’ll cancel with your old provider for you and your new SIM will come with a new phone number.

Useful link: Our guide to keeping your number

9. Try out your SIM within the first 14 days

Speedometer and mobile signal bars

Test coverage and speeds

Don’t take your eye off the ball once your new SIM card arrives, particularly if you’ve signed up to a deal with a contract length more than a single month, because you want to make sure you’re happy.

When you take any pay monthly SIM only plan you have the right to cancel it within the first 14 days to get a full refund, no matter if it’s a 12-month or 24-month plan. You should test your SIM as thoroughly as possible in this time.

If it comes with WiFi calling, give that a test by finding somewhere like a cupboard without signal and placing a call. If it’s got 5G, take that somewhere with known coverage to test it works.

Check your speeds, make phone calls inside your home and in the middle of the field. You should put the SIM to its limits to see any problems that arise. If you’re not happy you can then return it.

10. Keep on comparing all year round

A SIM card and magnifying glass

Prices drop year-on-yearCompare SIMs now

at simsherpa.com
(opens in new window)

If you’re looking to get the best possible deal then don’t get complacent once you’ve taken one plan. You should look around now and again to see if any better deals have come along.

That includes your current network if you’re on a 1-month deal or you’re on a provider that lets you switch between tariffs mid-contract. If something better comes along, why not ask to transfer onto it, if you don’t have to sign for longer?

The cost of mobile data has been going down quite rapidly, so while you might think you have the best possible deal, you’ll undoubtedly find something better in the future when you compare.

We’d also say keep an eye on your bills. Are you paying what you signed up for? You might think you’re on a great £5 deal. But it’s pointless if you’re wracking up £10 in extra charges. Keep monitoring and compare again.

Useful link: Compare SIM only deals

SIM only FAQs

It depends on the contract length. The most common options are 1 month, 12 months and 24 months. If you don’t want a commitment, choose a 1-month deal.

Yes. You’re not paying for a phone as part of your deal, so a network’s SIM only plans are always cheaper than their phone contracts.

Yes. But if your contract isn’t up, you will be charged for the remaining months, at a rate decided by the mobile network.

It depends what you’re looking for. There are better SIMs for price. There are better SIMs for network coverage and speeds. There are better SIMs for other added perks. Read our guides to help you compare.

If it’s pay monthly and you don’t use it, a network won’t mind how long you don’t use it, as you’re still paying for it. Usually on pay as you go, 3 to 6 months signals inactivity and they may de-activate it.

It depends on the mobile network and your contract length. On 1-month contracts, you’ll just have to pay to the end of your month. On longer ones, there’s usually a formula the network will apply based on the monthly cost and the months remaining.

At the end of your contract, your SIM only deal will continue to roll over month-to-month until you leave or change plans, which you're free to do at any time with no notice.

As long as that phone’s not locked to another network, your SIM will continue to work with the same phone number and plan as when it was in your old phone.

With old style pay as you go, you topped up with credit and your usage was charged out of that per minute, text and MB data. On SIM only, you receive a monthly allowance of minutes, texts and data for a fixed price.

Read mobile network reviews