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Mobile Phones

Best SIM only deals 2022

SIM only contracts can be much cheaper than regular mobile phone contracts.  But which SIM deals are the best? Read on to find out!

multi coloured sim cards

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, unlimited data and the very best deals.

Below the comparison table we've reviewed each SIM deal in more detail.

Best SIM only deals 2022

Mobile networkDataContractCost per month 
asda
Asda Mobile
3GB 1
month
£5 Get deal »
Full review
plusnet
Plusnet
4GB 1
month
£6 Get deal »
Full review
smarty
SMARTY
8GB 1
month
£7 Get deal »
Full review
vodafone
Vodafone
20GB
12
months
£8 Get deal »
Full review
id mobile
iD Mobile
10GB 24
months
£7 Get deal »
Full review
id mobile
iD Mobile
5GB 24
months
£6 Get deal »
Full review
smarty
SMARTY
12GB 1
month
£8 Get deal »
Full review
asda
Asda Mobile
5GB 1
month
£7 Get deal »
Full review
three
Three
12GB 12
months
£8 Get deal »
Full review
voxi
VOXI
15GB 1
month
£10 Get deal »
Full review

We select our top picks from offers available directly from each network. Our ranking takes into account contract length, data allowance and price.

SIM only contract reviews

asda mobile

Asda Mobile 3GB

SIM only deal

  • Monthly cost: £5
  • Length of contract: One-month rolling contract
  • Piggybacks on: Vodafone.

Get this deal »

Allowances

  • Data: 3GB
  • Minutes: Unlimited
  • Texts: Unlimited.

Other SIM only offers from Asda Mobile

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.

Get this deal »

↑ Comparison table

 

plusnet mobilePlusnet 4GB

SIM only deal

  • Monthly cost: £6
  • Length of contract: One-month rolling contract
  • Piggybacks on: EE.

Get this deal »

Allowances

  • Data: 4GB
  • Minutes: Unlimited
  • Texts: Unlimited.

Other SIM only deals from Plusnet

Extra data for existing Plusnet customers

Plusnet offers exclusive bonus deals to existing customers. These essentially act as upgrades on the existing plans, which all cost the same for Plusnet customers but come with 2GB of extra data.

So, in the case of the £6 per month deal we’ve featured, Plusnet customers will get 6GB of data rather than ‘just’ the 4GB that the package would normally get you.

Get this deal »

↑ Comparison table


smarty mobile

SMARTY 8GB

SIM only deal

  • Monthly cost: £7
  • Length of contract: One month rolling contract
  • Piggybacks on: Three.

Get this deal »

Allowances

  • Data: 8GB
  • Minutes: Unlimited
  • Texts: Unlimited.

Other SIM only offers from SMARTY

SMARTY offers a small selection of plans that are split into two groups. In addition to the deal we’ve featured, the main deals are:

SMARTY also offers what they call ‘data discount plans’, whereby you’re refunded for any unused data. These plans are:

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 a free month on your plan!

Get this deal »

↑ Comparison table

 

vodafoneVodafone 20GB

SIM only deal

  • Monthly cost: £8
  • Length of contract: 12 months
  • Piggybacks on: N/A.

Get this deal »

Allowances

  • Data: 20GB
  • Minutes: Unlimited
  • Texts: Unlimited.

Other SIM only offers from Vodafone

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.

Get this deal »

↑ Comparison table


id mobile

iD Mobile 10GB

SIM only deal

  • Monthly cost: £7
  • Length of contract: 24 months
  • Piggybacks on: Three.

Get this deal »

Allowances

  • Data: 10GB
  • Minutes: Unlimited
  • Texts: Unlimited.

Other SIM only offers from iD Mobile

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, then!

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.

Get this deal »

↑ Comparison table


id mobile

iD Mobile 5GB

SIM only deal

  • Monthly cost: £6
  • Length of contract: 24 months
  • Piggybacks on: Three.

Get this deal »

Allowances

  • Data: 5GB
  • Minutes: Unlimited
  • Texts: Unlimited.

iD Mobile review

Click here to find out more about iD Mobile.

Get this deal »

↑ Comparison table

 

smarty mobileSMARTY 12GB

SIM only deal

  • Monthly cost: £8
  • Length of contract: One-month rolling contract
  • Piggybacks on: Three.

Get this deal »

Allowances

  • Data: 12GB
  • Minutes: Unlimited
  • Texts: Unlimited.

SMARTY review

Click here to jump up to our earlier review and find out more about SMARTY.

Get this deal »

↑ Comparison table


asda mobile

Asda Mobile 5GB

SIM only deal

  • Monthly cost: £7
  • Length of contract: One-month rolling contract
  • Piggybacks on: Vodafone.

Get this deal »

Allowances

  • Data: 5GB
  • Minutes: Unlimited
  • Texts: Unlimited.

Asda Mobile review

Click here for our full review of Asda Mobile and its other top deals.

Get this deal »

↑ Comparison table


three mobile

Three 12GB

SIM only deal

  • Monthly cost: £8
  • Length of contract: 12 months
  • Piggybacks on: N/A.

Get this deal »

Allowances

  • Data: 12GB
  • Minutes: Unlimited
  • Texts: Unlimited.

Other SIM only offers from Three

* Six months at £11 per month, then the remaining 18 months at £22 per month.

Cheap data roaming with Three

Three’s SIM only deals also include Go Roam, the network’s data roaming service. Unlike most other networks, Three’s no-extra-charge roaming doesn’t just apply in Europe – it applies to a total of 71 destinations around the world, including the USA.

Their SIMs are also 5G-ready, which means that anyone with a 5G-enabled phone can access the frankly ridiculous speeds that you get with the next generation of internet data.

Get this deal »

↑ Comparison table


voxi mobile

VOXI 15GB

SIM only deal

  • Monthly cost: £10
  • Length of contract: One-month rolling contract
  • Piggybacks on: Vodafone.

Get this deal »

Allowances

  • Data: 15GB (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. You can check out all the plans here.

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)
  • Instagram
  • Pinterest
  • Snapchat
  • Twitter
  • WhatsApp.

Get this deal »

↑ Comparison table

 

Why should you get a SIM only deal?

These are the things to consider when you’re thinking about signing up for a SIM only contract:

  1. 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.

  2. 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.

    Finally, if you want to buy an iPhone, Apple has a little-known service to buy a brand new iPhone and spread the cost across 20 months with 0% interest.

    With the exception of rare flash sales, this is the cheapest way to buy a new iPhone. Find out more about the payment plan here.

  3. 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.

  4. 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. Fortunately, this site has a really handy tool where you can select the networks you’re moving to and from, and it tells you exactly 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 this tool.

Unsure if SIM only is right for you? Check out our guide to getting the best phone contract.

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