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Best SIM only deals

Compare SIM only contract deals

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Best SIM only deals

SIM only deals

SIM only deals are becoming increasingly popular, and more and more mobile network providers are jumping on the bandwagon and offering bargain tariffs.

Best PAYG SIM only deals

Provider Data Monthly cost
VOXI Unlimited £30 See deal
O2 60 GB £20 See deal
VOXI 100 GB £20 See deal

*All deals come with unlimited calls and texts

See more PAYG SIM only deals

Best 1 month SIM only deals

Provider Data Monthly cost
Three Mobile Unlimited £30 See deal
O2 Unlimited £36 See deal
Vodafone Unlimited £37 See deal
iD Mobile 20 GB £7 See deal
TalkMobile 6 GB £5.95 See deal

*All deals come with unlimited calls and texts

See all 1 month SIM only deals

Best 12 month SIM only deals

Provider Data Monthly cost
Three Mobile Unlimited £19 See deal
O2 Unlimited £33 See deal
Vodafone Unlimited £27 See deal
Sky mobile 80 GB £33 See deal
iD Mobile 20 GB £7 See deal

*All deals come with unlimited calls and texts

See all 12 month SIM only deals

Best 24 month SIM only deals

Provider Data Monthly cost
Three Mobile Unlimited £18 See deal
O2 125 GB £18 See deal
Vodafone 80 GB £23 See deal
iD Mobile 25 GB £7 See deal

*All deals come with unlimited calls and texts

See all 24 month SIM only deals

What are SIM only deals?

Unlike phone contracts, SIM only deals are contracts that just give an allowance of minutes, texts and data. They depend on you having a handset already.

Generally, SIM only deals tend to be either one month or twelve months in length. With the latter, you’re locked into paying your chosen tariff for a year. Conversely, a one-month contract – also known as a rolling contract – involves you just purchasing a 30-day deal. At the end, you have a few options: you can auto-renew; you can modify your package by upgrading or downgrading (for example, if you know you’ll need a higher data allowance next month); or, if you find a better mobile phone deal with another provider, you’re free to leave.

Once you’ve chosen a tariff, you’ll be sent a SIM card that’ll fit your phone, whether you have a Standard, Micro or Nano SIM slot.

What are the benefits of SIM only deals?

  • You’re not forced to get a new phone. Many of us are content with our devices, not feeling the need to have the latest release. SIM only deals mean you can stick with your trusted handset (because it’s working just fine thanks!).
  • SIM only deals allow you to be far more flexible, with contracts of one to twelve months.
  • If you can afford to buy a phone outright, it’ll work out cheaper overall than purchasing it on a monthly contract.
  • SIM only deals have less-stringent credit checks to pass than pay monthly contracts.
  • Because you’re only paying for the tariff rather than a fee for the handset, it’s much cheaper – it’s common to see SIM only phone deals with unlimited texts and calls, along with 10GB of data for less than £10 a month (long gone are the days of spending £10 credit on your Nokia 3310 just to text your mates hello!).
  • When you compare mobile phone deals with usave, you can still access gifts and rewards.  

What are the drawbacks of SIM only deals?

Of course, SIM only deals do have their disadvantages as well. You have to own the phone outright first, which can mean a hefty upfront cost, especially if you want the latest releases.  

In addition, don’t forget that a SIM only deal on a twelve-month contract is still a contract. It must be paid in full. Therefore, should you want to exit early, you’ll have to settle the remainder, which could cost you more than it’s worth. If you don’t fancy entering into a long phone contract, our advice is to compare SIM only deals with short-term contracts instead.  

Should I switch to a SIM only deal?

Switching to a SIM only plan can be a great way to save on your monthly expenditure. If you’re satisfied with your current handset and feel no need to change, then you don’t need to pay the premium of a new phone. Alternatively, if you have a SIM-free phone already – perhaps you’ve bought it outright or a very kind pal has passed it on – you’ll have to look for SIM only deals.

Which networks offer SIM only deals?

SIM only deals are available on most UK networks. And often, this is where some of the lesser-known carriers come up trumps. Giffgaff, Plusnet, and iD Mobile, to name a few, are known as piggyback providers, meaning they pay a fee to use the service infrastructure of the Big Four (EE, O2, Three and Vodafone). As such, the quality of your coverage will be the same.

These smaller providers can offer bargain deals at extremely competitive prices. Your only compromise may be that you won’t have access to all of the same perks you’d otherwise get with a major carrier (think O2 Priority or VeryMe), nor may customer services be quite so developed – so do weigh this up when looking for a new SIM deal. However, it is worth knowing that year on year smaller providers are highly commended for their cheap mobile deals, including some of the cheapest SIM only deals on the market.

How much data do I need on my SIM?

When comparing SIM only deals, you'll come across a range of data allowances on offer. These start from basic 0GB plans (calls and texts only), all the way up to unlimited data allowances, which are the most comprehensive, and also the most expensive, SIM only deals you can get. 

While we'd rarely every recommend getting a no data SIM, if you only use the internet sparingly on your smartphone, for example to browse a few web pages or send a couple of emails, then we'd suggest going for a cheap 1GB or 2GB plan. 

According to Ofcom, mobile users in the UK consumed 4.5GB of data per month in 2020. So, if you think you use the internet on your phone just as much as the next person does, but no more, then you could get away with a 5GB data plan.

However, if you're a bit of a social media addict, or you like to stream music from the likes of Spotify, we'd recommend going for at least 10GB of data per month. And if you like to stream Netflix or any other video on your phone, you'd need a much healthier data allowance - perhaps around 100GB.

How long does a SIM-only contract last?

There is no one set rule for how long a SIM-only contract should last, with most providers giving you the option of both short and flexible rolling contracts as well as longer term plans. 

A few providers still offer pay-as-you-go (PAYG) SIM deals, in which you pay for the initial data/minutes/texts allowance and then top up whenever you run out.

However, the most common SIM-only deals are now 1-month plans, also known as rolling monthly contracts, in which your allowance is refreshed each month but you’re free to leave with just a month’s notice.

A growing number of network providers are also offering 12 or 24-month contracts. These longer plans will often allow you to save a few quid each month, but you’ll have to commit to the entire term or else you could end up paying costly exit fees.

Can I keep my number if I switch to a SIM only deal?

So long as you’re switching to another UK number, you can always keep your number. Whether you’re going from a pay monthly contract to a SIM only deal or switching networks altogether, you can keep your numerical identity by a method called Porting. We’ve got a whole guide on porting your mobile to a new network.

Last reviewed: 06 July 2023

Next review: 06 August 2023