The Best SIM Only Deals in April (2024)

All the UK's best SIM Only deals this month, compared in one place

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We’ve done the hard work for you and rounded up the best SIM Only deals in the UK this month, across all networks and retailers. 

Switching to a SIM only deal is a simple and fast way to reduce your monthly phone bill when you reach the end of your mobile contract, or if you’ve bought a SIM free phone without a contract and need a great value plan.

If you’re happy with your current phone, you can switch your plan to a SIM only plan either with your current network if they offer you a decent price, or choose a new one from our picks below.

Here are the very best SIM Only deals out there this month.

45p a month bargain SIM

Lebara Mobile | 1GB Data | 250 minutes & unlimited texts | 1 month | 45p a month

Yes you read that right, 45p a month.  With 1GB of data, 250 minutes and unlimited texts, this deal is a steal. The 45p promotion applies for the first 3 months, after which you can cancel or continue at £3.99 a month.
Grab this deal from Lebara mobile

Voxi | 15GB data | Unlimited minutes & texts | 30 day contract | £10 a month

15GB for £10 on a 30 day rolling plan from Voxi. Great deal and runs on the Vodafone network so covers most of the UK. You also get unlimited social media data use on most social media apps.
Grab this deal from Voxi

6GB for £6

Smarty | 60GB Data | Unlimited minutes & texts | 1 month | £8 a month

This deal from Smarty is just £6 a month on a short rolling 30 day contract. For that you get 6GB of data plus unlimited calls and texts, inclusive EU roaming and there’s no credit check.
Grab this deal from Smarty

6GB for £5.99 a month | 1 month plan

Lebara | 6GB Data | Unlimited minutes & texts | 1 month | £5.99 a month

Lebara SIM plans are so much better than they used to be, with increased data allowances that bring them up to the level of some of the bigger networks. £5.99 bags you 6GB of data plus unlimited calls and texts. You also get 100 international minutes to over 40 countries.
Grab this deal from Lebara

25GB for £7 a month | 1 month plan

iD Mobile | 25GB Data | Unlimited minutes & texts | 1 month | £7 a month

£7 for 25GB, not bad at all. And no annual price increases. 1 month contract and includes unlimited calls and texts.
Grab this deal from iD

120GB for £12 a month | 1 month plan

iD Mobile | 120GB Data | Unlimited minutes & texts | 1 month | £12 a month

No annual price rises and this £12 a month deal gets you a huge 120GB of data on a rolling 1 month contract. Includes EU data roaming too.
Grab this deal from iD

32GB for £8 a month

O2 | 32GB data | Unlimited minutes & texts | 12 months | £8 a month

This deal on O2 bags you 32GB of data at just £18 a month and being on O2 it includes EU roaming and O2 Priority which gets you discounts on tickets and events.
Grab this deal from O2

Unlimited Data for £16

Smarty | Unlimited Data | Unlimited minutes & texts | 1 month | £16 a month

The best unlimited data deal out there right now, £16 a month from Smarty and includes unlimited calls and texts, plus inclusive EU roaming.
Grab this deal from Three

These are the best SIM only deals we’ve found this month, but if you want to compare even more, head this way…

About our deals

We sort through thousands of deals every day to find the best prices available from trustworthy retailers. This article contains affiliate links where Direct Mobiles may receive a commission on any sales we generate from it and this is how this site is funded. This is no way impacts our recommendations as our ultimate goal is to only ever recommend the best value deals for our readers. You can learn more here. If we recommend a deal, it is because we truly believe it to be worth looking at.

What is a SIM Only deal?

A SIM Only deal is a mobile tariff offer of minutes, text and data (or any combination) that does not include a mobile phone. Therefore you would need to have a mobile phone already to be able to take advantage of one these offers. If you ordered a SIM Only deal you would expect to receive a SIM card only and nothing else.

SIM Only deals: are they worth it?

SIM only deals tend to be contracted for a shorter period that a pay monthly mobile plan, which allows you to be more flexible about your choice of phone. You may continue to use an older, perfectly serviceable handset or purchase one in a different way. Currently you could choose to by a mobile phone on finance and pay it off monthly, separately from the SIM Only contract, trade in an old handset or indeed buy a second hand handset. SIM Only deals tend to attract two distinct types of customers, customers who are looking for value and customer who tend to change their handsets more often.   

SIM only deals: are they cheaper than phone contracts?

SIM Only deals either have larger allowances of minutes text and data, or they are significantly cheaper than normal contracts. The networks are able to do this because in a normal 24 month contract deal, a portion of the monthly line rental is to cover subsidising the mobile phone, to make it more attractive when you connect.  They also tend to be for a shorter periods of time, you can get SIM only deals on 30 day rolling contracts as well as for 12 months. Once you are out of your minimum contract time you would normally have to give 30 days notice.

How much data will I need?

Good question, how much do you use your phone to access the internet, social media, listen to music, watch you tube, Netflix or other video streaming services? Don’t know? If you are leaving a network to get a great SIM only deal you can ask for your last 3 months average data use.  If you are completely new to mobile then it would be good to know that the average user, uses 2.5gb of data per month. Most networks will allow you to move up a tariff so if you find in the 1st month you have used more than your data allowance then move up, pay more per month and get some more data.

More SIM Only FAQs

You may see different variations of the SIM Only contracts displayed, no contract, 30 day contract and 12 month contract. We feel the no contract versions are slightly misleading as more often than not there is a 30 day notice period, therefore whether it is no contract or 30 day contract in both cases you would have to give notice the day you connected to only get 30 days of service. 12 months SIM only contracts generally have greater allowances or are cheaper per month because you have agreed to a minimum of 12 months.

Whether you are in or out of contract you would need to contact your network customer services for a porting authorisation code ( PAC). If you are out of contract this will trigger the 30 days notice period, you will no doubt have to give your current network, you will get the code and then a final bill. If you are in contract and you ask for a PAC code there may be charges to end the contract early, if you happen to ask for a PAC code at more or less exactly 30 days from your contract end then you will get the code and a final bill.

Get your PAC code from EE

  • Call 150 from an EE mobile phone
  • Call 079 5396 6250 from any other phone (mobile or landline)

Get your PAC code from Three

  • Call 333 from a Three phone
  • Call 033 3338 1001 from any other phone (mobile or landline)

Get your PAC code from O2

  • Call 202 from an O2 phone
  • Call 034 4809 0222 from any other phone (mobile or landline)

Get your PAC code from Virgin Mobile

  • Call 789 from a Virgin Mobile phone
  • Call 034 5600 0789 from any other phone (mobile or landline)

Get your PAC code from Vodafone

  • Call 191 from a Vodafone phone
  • Call 033 3304 0191 from any other phone (mobile or landline)

Get your PAC code from BT Mobile

  • Call 150 from a BT Mobile phone
  • Call 0800 800 150 from any other phone (mobile or landline)

Get your PAC code from Plusnet Mobile

  • Call 500 from a Plusnet Mobile phone
  • Call 080 0013 2632 from any other phone (mobile or landline)

Get your PAC code from iD Mobile

  • Call 7777 from an ID Mobile phone
  • Call 033 3003 7777 from any other phone (mobile or landline)

Get your PAC code from Tesco Mobile

  • Call 4455 from a Tesco Mobile phone
  • Call 034 5301 4455 from any other phone (mobile or landline)

Get your PAC code from Sky Mobile

  • Call 033 0041 2639 from Sky Mobiles, phones registered to other networks and landlines

Get your PAC code from giffgaff

giffgaff doesn’t operate customer support helplines. However, you can get a PAC code from giffgaff by mailing them using giffgaff’s contact form.

Get your PAC code from VOXI

You can only contact the network via Twitter, web chat and Facebook Messenger. To get your PAC code, head to VOXI’s contact page.

Get your PAC code from SMARTY

SMARTY doesn’t have any customer service helplines. To get your PAC code, log into your SMARTY account.

Get your PAC code from Lebara

Ring 5588 from your Lebara mobile. Rates are charged at 19p per call.

Ring 020 7031 0791 from all other networks or from your landline.

The SIM is short for subscriber identity module, great answer for a pub quiz! Good news is that the SIM over time has got smaller and smaller. Back in the day they were the size of a credit card and now most phones are either a micro sim or a nana sim. The good news is the networks know this and will provide a sim card that will have a push out to fit the phone of your choice. If you need to go back up to a micro from a nano I would suggest contacting your network for a replacement sim to ensure that you have one that fits correctly.

If you have more time take a look at our article, ‘What is the best mobile phone network?‘ which cover this in great detail, but the short version is that Mobile Networks (MNO) have great deals if you go direct but they tend to be a bit less flexible than the smaller Virtual Mobile networks (MVNO). If you want to know more about the differences between networks, take a look at our article, ‘What is the difference between a Mobile and a Virtual Mobile Phone Network?’. What do we mean by saying less flexible?  They tend to have 30 day rolling and 12 month contracts that have a lot of perks, EE give you 6 months of free Apple Music with certain deals which alone is worth £60.00.  O2 SIM Only deals allow you take advantage of O2 priority. MVNO’s tend to offer simpler propositions which concentrate on value. 


Get all the benefits of having a lengthy contract like 3 months free access to BT sports and inclusive minutes and texts to use when you are abroad in Europe, add this to the amazing 4G speeds in this network and you are in for a winning combination.


The network built for data and still the only major player who has unlimited data plans on SIM only.


One of the oldest networks with great coverage, comes with a no quibble 30 day guarantee, if you are not happy with your SIM only they will cancel your contract.


Great sim only deals with all the benefits of a normal contract, you will still get access to O2 priority, great if you like sports and entertainment.


One of the very early SIM Only networks, packed with all the features you would expect and customer services which is managed by the giffgaff community. They also give you extra goodies if you introduce your friends and family.


No contract, no credit check on pay as you go and 4G as standard on all plans. iD Mobile runs on the Three network.


One of the latest SIM Only networks which offers unlimited UK minutes and texts which discounts your next months line rental if you have not used all your data. Smarty runs on the Three network.


If you are under 30 this is the network for, you not data charges for using social media and three simple plans to choose from. Voxi is owned and operated by Vodafone.

Tesco Mobile

If you want all your eggs in one basket then Tesco is for you. Save on your shopping while talking to your friends and family. Tesco Mobile runs on the O2 network.


Unmatched value with data, national and international calls packed into one plan.


Faster 4G on average compared to other networks with free Whatsapp and Facebook messaging included. Virgin runs on the EE network.


Great if you want to rollover all your unused data every month.


Great value, simple no nonsense sim only deals with the addition of smart cap to manage your spending. Plusnet runs on the EE network.

If we concentrate on the coverage for the MNO this will cover the MVNO’s as  well, if you take a look at our article what is the difference between a Mobile and a Virtual Mobile Phone Network? There is a non-exhaustive list of what MVNO’s  use what network. When you are connecting you should be able to do a coverage check during the application process. If you do buy a SIM only deal and you do have coverage issues all online sales are covered by distance selling regulations so you will be able to return and cancel.

If you have a handset that was initially supplied by a network directly it is likely that the handset will be locked to the network. Therefor it would be necessary to unlock the handset before using it with a SIM only deal with another provider.  See the guides below to help you to do this.


All devices sold by EE are locked to EE. This means they’ll only work with an EE SIM card – they won’t work with another network’s SIM card (apart from Virgin Mobile). Depending on your device, it’ll unlock automatically or you’ll need a code from the original network to unlock it.  You can call EE using 150 from your handset or call 0800 079 8586

  1. Any iPhone or iPad sold directly by EE, on or after 1 September 2015, will be unlocked automatically once it reaches 18 months old.*
  2. Google Pixel phones (all variants) automatically unlock themselves on day 721 from point of activation. You’ll receive a device configuration notification to confirm when it is unlocked.
  3. All other devices require a code to unlock them for use with other networks. Please contact the original network to obtain a code.

*replacement devices will be unlocked 18 months from the point they are first used

This applies to pay monthly, pay as you go and small business devices – not corporate devices. Devices connected to corporate accounts are not eligible for unlock. To raise an unlocking request for a corporate device, contact your Account Manager.

EE aim to unlock all devices within 72 hours. If they need to contact the manufacturer to get a code, it may take 10 days. But they’ll be in touch if that’s the case.


If you’re on an O2 Pay Monthly tariff, you can unlock your phone or tablet at any time, for free.  

This doesn’t affect your contract – you’ll still need to see out the rest of it, depending on your device and tariff.

The only way to unlock your phone or tablet is by using My O2 online or via the main menu of the My O2 app. Once it’s unlocked, we’ll text you to let you know.

If you’ve got an iPhone or an iPad, you’ll need to connect it to iTunes once you’ve put a non-O2 sim into the device. iTunes will then tell you the phone or tablet is unlocked.

For all other phones and tablets, you’ll get a text with an unlocking code. Simply enter this into your device and follow the instructions.


The Network Unlock Code or NUC (sometimes called a Network Unlock PIN or NUP, or Network Control Key or NCK) allows you to unlock a mobile phone from its original network.  You can call Vodafone using 191 from your Vodafone handset or call 03333 040 191

It’s free for consumer and small business customers to request a NUC.

To get your unlock code, Vodafone will need some information from you first. Once they’ve received this information, they will contact you within 48 hours. Sometimes they may need to get in touch with your phone’s manufacturer, which can take up to 10 working days.

Please note: If you’re no longer a Vodafone customer, you can still request your NUC from Vodafone as long as you previously used your phone on their network.


If you have purchased directly from Three and this is after 1st January 2014 your handset will already be unlocked.


Handsets that are used to access Virgin Mobile’s services are locked to the Network. If you wish to unlock your handset from the Network you will need to contact the Virgin Team on 0800 052 0800 and pay the Charges for unlocking your handset as set out in the Tariff Table. You will also need to have paid all Charges owing on your account before they unlock your handset. For security reasons you will also need to register the handset you wish to unlock with them before they unlock it for you.

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