Best SIM only deals 2023
SIM only contracts can be much cheaper than regular mobile phone contracts. But which SIM deals are the best? Read on to find out!
What is a SIM only deal?
SIM only deals allow you to pay only for usage (minutes, texts and data) without buying a new mobile phone.
They are very similar to pay as you go (PAYG) offers. However, SIM only plans last for a set period of time (between 30 days and 24 months) and renew after expiring.
We review mainly SIM only deals in this guide, but we may include some PAYG deals too. The focus is on low-cost plans, mobile data and the very best deals.
Compare SIM only deals
Best SIM only deals 2023 |
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| Mobile network | Data | Contract | Cost per month | |||
|---|---|---|---|---|---|---|
Asda Mobile |
3GB |
1 month |
£5 |
Full review |
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Virgin Mobile |
20GB |
1 month |
£8 |
Full review |
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VOXI |
30GB |
1 month |
£10 |
Full review |
||
Vodafone |
20GB |
12 months |
£8 |
Full review |
||
iD Mobile |
10GB |
1 month |
£7 |
Full review |
||
Three |
12GB |
12 months |
£14 |
Full review |
||
giffgaff |
20GB |
1 month |
£10 |
Full review |
||
SMARTY |
30GB |
1 month |
£10 |
Full review |
||
Tesco Mobile |
60GB |
24 months |
£15 |
Full review |
||
O2 |
150GB |
24 months |
£19.99 |
Full review |
||
Lebara |
5GB |
12 months |
£4.50 |
Full review |
||
| Information correct at time of writing. Prices subject to change. Please check websites for details | ||||||
We select our top picks from offers available directly from each network. Our ranking takes into account contract length, data allowance and price.
For this reason, there will be some popular brands not included in the table as their offers weren’t strong enough. It’s still worth checking them out via these links (EE, BT Mobile & Sky Mobile).
SIM only contract reviews
Asda Mobile 3GB
SIM only deal
- Monthly cost: £5
- Length of contract: One-month rolling contract
- Piggybacks on: Vodafone.
Allowances
- Data: 3GB
- Minutes: Unlimited
- Texts: Unlimited.
Other SIM only offers from Asda Mobile
- 12GB, unlimited minutes and unlimited texts for £10 per month | Get this deal
- 25GB, unlimited minutes and unlimited texts for £15 per month | Get this deal
- See the rest of Asda Mobile’s SIM only deals
Spending caps with Asda Mobile
Worried that you’ll exceed your monthly allowance and rack up a huge bill? Worry not, as Asda Mobile lets you place a cap on your spending, so you’ll never end up splashing the cash without realising.
Virgin Mobile 20GB
SIM only deal
- Monthly cost: £8
- Length of contract: One-month rolling contract
- Piggybacks on: O2.
Allowances
- Data: 20GB
- Minutes: Unlimited
- Texts: Unlimited.
Other SIM only deals from Virgin Mobile
- 30GB, unlimited minutes and unlimited texts for £10 per month | Get this deal
- 15GB, unlimited minutes unlimited texts for £7 per month | Get this deal
- See the rest of Virgin Mobile’s SIM only deals
Data Rollover with Virgin Media
All of Virgin Mobile’s SIM only plans now come with Data Rollover. In other words, if you don’t use all the data from one month’s allowance, it’ll be added on top of your allowance next month (just note that it will only roll over once).
VOXI 30GB
SIM only deal
- Monthly cost: £10
- Length of contract: One-month rolling contract
- Piggybacks on: Vodafone.
Allowances
- Data: 30GB (unlimited for social media)
- Minutes: Unlimited
- Texts: Unlimited.
Other SIM only offers from VOXI
VOXI only offers a few plans, most of which come on similar terms with exactly the same allowances (including unlimited social data) – apart from the data. Some plans also include unlimited video streaming on YouTube, Netflix, Prime Video, My5 and TikTok. You can check out all the plans on VOXI’s website.
Unlimited social data and video streaming for VOXI customers
It’s worth noting that when VOXI say you get unlimited social data, this only applies to the following apps, and excludes video and voice calls:
- Facebook (including Facebook Messenger)
- Snapchat
- WhatsApp.
Vodafone 20GB
SIM only deal
- Monthly cost: £8
- Length of contract: 12 months
- Piggybacks on: N/A.
Allowances
- Data: 40GB
- Minutes: Unlimited
- Texts: Unlimited.
Other SIM only offers from Vodafone
- 20GB, unlimited minutes and unlimited texts for £8 per month (12 months) | Get this deal
- 6GB, unlimited minutes and unlimited texts for £7 per month (12 months) | Get this deal
- See the rest of Vodafone’s SIM only deals
Anything else to know?
Vodafone customers are able to get exclusive offers on the network’s VeryMe Rewards app. Like O2’s Priority Moments, VeryMe has exclusive offers and giveaways that range from the likes of a free coffee to access to ticket presales.
iD Mobile 10GB
SIM only deal
- Monthly cost: £7
- Length of contract: One-month rolling contract
- Piggybacks on: Three.
Allowances
- Data: 10GB
- Minutes: Unlimited
- Texts: Unlimited.
Other SIM only offers from iD Mobile
- Unlimited data, unlimited minutes and unlimited texts for £18 per month | Get deal
- 200GB, unlimited minutes and unlimited texts for £15 per month | Get deal
- See the rest of iD Mobile’s SIM only offers
Extra perks for iD Mobile customers
There are a fair few added perks that come with being a SIM only customer with iD Mobile.
For starters, you can cap your out-of-plan spending (how much you’re willing to spend if you’ve used all your allowances) to as little as £0. No more nasty surprises at the end of the month for you.
What’s more, all iD Mobile plans come with Data Rollover – a free feature that transfers any unused data from one month to the next, meaning you never miss out on using what you’ve paid for.
Three 12GB
SIM only deal
- Monthly cost: £14
- Length of contract: 12 months
- Piggybacks on: N/A.
Allowances
- Data: 12GB
- Minutes: Unlimited
- Texts: Unlimited.
Other SIM only offers from Three
- 25GB, unlimited minutes and unlimited texts for £14 per month (24 months) | Get deal
- 120GB, unlimited minutes and unlimited texts for £16 (24 months) | Get deal
- See the rest of Three’s SIM only offers
Data roaming with Three
Three’s SIM only deals include Go Roam, the network’s data roaming service. There’s a daily roaming charge: £2 in Go Roam in Europe destinations and £5 in Go Roam Around the World destinations. Check Three’s site for more info.
giffgaff 20GB
SIM only deal
- Monthly cost: £10
- Length of contract: One-month rolling contract
- Piggybacks on: O2.
Allowances
- Data: 20GB
- Minutes: Unlimited
- Texts: Unlimited.
Other SIM only offers from giffgaff
- 35GB, unlimited minutes and unlimited texts for £15 per month | Get deal
- 100GB, unlimited minutes and unlimited texts for £20 per month | Get deal
- See the rest of giffgaff’s SIM only offers
giffgaff goodybags
giffgaff offers loads of options via their goodybags. And if you opt for a golden goodybag (where you agree to keep the monthly contract rolling), you’ll get even better deals.
SMARTY 30GB
SIM only deal
- Monthly cost: £10
- Length of contract: One-month rolling contract
- Piggybacks on: Three.
Allowances
- Data: 30GB
- Minutes: Unlimited
- Texts: Unlimited.
Other SIM only offers from SMARTY
- 8GB, unlimited minutes and unlimited texts for £7 per month | Get deal
- 12GB, unlimited minutes and unlimited texts for £8 per month | Get deal
- 100GB, unlimited minutes and unlimited texts for £12 per month | Get deal
- See the rest of SMARTY’s SIM only offers
SMARTY referral scheme
SMARTY also runs a refer-a-friend scheme. Every time you refer a friend to join the network, you’ll both get £10 gift card!
Tesco Mobile 60GB
SIM only deal
- Monthly cost: £15
- Length of contract: 24 months
- Piggybacks on: O2.
Allowances
- Data: 60GB
- Minutes: Unlimited
- Texts: Unlimited.
Other SIM only offers from Tesco Mobile
- 12GB, unlimited minutes and texts for £10 per month (24 months) | Get this deal
- See the rest of Tesco Mobile’s SIM only deals
Bonus Clubcard points with Tesco Mobile
As you might expect, Tesco Mobile customers can also earn Clubcard points when they pay their monthly bill.
Tesco Clubcard is one of the most popular loyalty card schemes and you can redeem your points with a whole load of companies, including restaurants, airlines and, of course, Tesco itself.
As well as earning one point for every £1 you spend on a pay monthly contract, you can also use your Clubcard vouchers to knock money off your phone bill.
O2 150GB
SIM only deal
- Monthly cost: £19.99
- Length of contract: 24 months
- Piggybacks on: N/A.
Allowances
- Data: 150GB
- Minutes: Unlimited
- Texts: Unlimited.
Other SIM only offers from O2
- 15GB, unlimited minutes and texts for £15 per month (24 months) | Get this deal
- See the rest of O2’s SIM only deals
Free roaming with O2
One of the biggest perks you get with a SIM only deal with O2 is that it allows you to use your data (up to 25GB) abroad without paying any extra costs.
Lebara 5GB
SIM only deal
- Monthly cost: £4.50
- Length of contract: 12 months
- Piggybacks on: Vodafone.
Allowances
- Data: 5GB
- Minutes: Unlimited (plus 100 international minutes to 42 countries)
- Texts: Unlimited.
Other SIM only offers from Lebara
- 20GB, unlimited minutes and texts (plus 100 international minutes to 42 countries) for £9 per month (12 months) | Get this deal
- 30GB, unlimited minutes and texts (plus 500 international minutes to 42 countries) for £13.50 per month (12 months) | Get this deal
- See the rest of Lebara’s SIM only deals
International calls and roaming
Lebara is a great option for international students, as most of the plans include 100+ minutes to 42 countries outside of the UK. On top of that, they offer free roaming in the EU and India.
Why should you get a SIM only deal?
These are the things to consider before signing up for a SIM only contract:
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Do you need a new mobile phone?
The main question to ask yourself when considering a SIM only deal is, “Do I need or want a new phone?”.
If the answer is “no”, then a SIM only deal is almost certainly the best and cheapest option for your new contract.
However, if the answer is “yes”, things are slightly more complicated.
Taking out a SIM only contract and buying a phone outright is often cheaper than a standard pay monthly contract with a phone included – but not always.
Occasionally mobile networks run mobile phone deals on a pay monthly contract that is cheaper than buying a phone and SIM only contract separately.
Before you go for a SIM only deal, take a look at the best pay monthly contracts.
Once you’ve found a good pay monthly deal, work out the lifetime cost of the contract (the monthly cost multiplied by the number of months). Then compare it with the lifetime cost of an equivalent SIM only contract, plus the cost of buying a phone separately.
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Learn how to buy a cheap phone
Although buying a phone upfront (rather than on contract) is usually cheaper, you’ll need to have several hundreds of pounds spare.
If you’ve got a particular phone in mind, head to Idealo. Here you can search for the phone you’re after and it’ll show where you where it’s selling for the lowest price.
Make a note of the cheapest four or five retailers. Then head over to TopCashback and Quidco to see if you can earn cashback at a retailer selling the phone you want.
Alternatively, head to eBay for a bargain. As well as brand new mobile phones, you’ll find second-hand and refurbished phones to choose from.
Check out our guide to getting an eBay bargain for more tips.
With the exception of rare flash sales, this is the cheapest way to buy a new iPhone.
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Is your phone unlocked?
Whether you’re planning to buy a new phone or keep your existing one, you’ll need to make sure it’s unlocked for use on all mobile networks.
As of December 2021, it’s now illegal for networks to sell phones that are locked. If you’ve bought a phone since then, you should be in the clear. However, if you bought your phone before this time, you may need to unlock it.
Fortunately, this is often free. We’ve got a super useful guide to unlocking your phone.
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How much data, minutes and texts do you need?
Unlimited minutes, data and texts all sound appealing. In reality, you’ll be paying through the nose for things that you don’t actually need.
With iMessage, WhatsApp, Facebook Messenger, Instagram and Snapchat all offering free messaging services, the number of actual texts that you send is lower than ever. So you probably don’t need unlimited texts.
As for minutes and data – well, we can’t really say how much you need. That said, you should be able to get WiFi at home, at uni and possibly at work. If you’re careful, you shouldn’t need much more than 5GB of mobile data.
If you often call people on FaceTime, WhatsApp or any other internet calling service, you shouldn’t need many minutes, either. Just make sure you don’t make these calls when you’re using data, as it’ll rinse your allowance!
And if you’re still unsure how much you need, you can check your data, calls and text usage in the online account you have with your network. Alternatively, billmonitor is a free (and Ofcom-approved) service which analyses your bills and tells you how much you use for you.
SIM only FAQs
Can I keep my number with SIM only contracts?
Yes. Whether it’s SIM only, pay monthly or pay as you go, you can always transfer the number from one SIM to another for free.
Ask your current mobile network for your PAC code, given to you immediately over the phone or within two hours via text.
Each network has a slightly different process for giving out PAC codes. PACCodes.co.uk has a handy tool where you can select the networks you’re moving to and from, and it tells you what to do.
Are the best SIM only deals available to everyone?
Unfortunately not. The very best SIM only offers are usually only available to new customers.
However, as we explain in our guide to getting the best phone contract, being an existing customer can be used to your advantage.
Networks are desperate not to lose customers. Call up your network and ask them to match an offer that’s exclusive to new customers.
Explain that you’ve been a loyal customer of theirs for months/years, and that you’re considering going elsewhere having seen a better deal.
Is there a credit check for SIM only contracts?
A normal phone contract is a financial agreement. Networks often run a credit check on new customers to review their credit score.
For SIM only contracts, it depends on the deal you’re going for.
If you’re paying for the entire term of the contract in advance, there won’t be a credit check. This usually applies to 30-day contracts, but it’s still worth checking with the network if you’re worried you’ll fail a potential credit check.
If you’re going for a longer-term deal (like a 12 or 24 month contract) they’re more likely to conduct a credit check on you. This is because you won’t be paying upfront.
To improve your credit score check out our guide to credit ratings.
Why has the price of my SIM only contract gone up?
The cost of a phone contract often goes up over time in line with inflation.
SIM only contracts are no exception. But if you’re on a long-term contract, your network should notify you if and when they intend to increase the price.
The price increase is usually only a couple of percent, so it often won’t make a huge difference to the affordability of the plan. But it’s always worth comparing the latest SIM only deals at the time.
What is a rolling contract?
This is a contract that automatically renews at the end of its term. Most 30 day SIM only contracts are rolling by default, otherwise you can opt-in to having it roll.
In most cases, you’ll pay in advance and can therefore cancel at any time.
What is piggybacking?
Most mobile networks are actually ‘virtual networks’. This means they don’t operate on their signal.
Instead, they ‘piggyback’ on the signal provided by one of the four ‘actual’ mobile networks in the UK: EE, Three, O2 and Vodafone.
Every other mobile network piggybacks on one of these four. You can check the coverage of each network in your area using Ofcom’s tool.
Unsure if SIM only is right for you? Check out our guide to getting the best phone contract.
