We use cookies to allow us and selected partners to improve your experience and our advertising. By continuing to browse you consent to our use of cookies as per our policy which also explains how to change your preferences.

How to choose the best mobile phone deal

Getting the best sim-only phone deal

By Tom Morgan

Article 4 of 4

Put us to the test

Our Test Labs compare features and prices on a range of products. Try Which? to unlock our reviews. You'll instantly be able to compare our test scores, so you can make sure you don't get stuck with a Don't Buy.

Getting the best sim-only phone deal

Thinking of signing up for a Sim-only deal? Read our expert guide to Sim-only mobile phone contracts to find out if Sim-only is right for you.

If you own your mobile phone outright, or have enough cash to buy a new phone outright, then you might want to consider a Sim-only mobile phone deal.

As the name suggests, you pay for a new Sim-card for your phone - rather than an entirely new handset. Sim-only packages can potentially save you some money, with companies such as Giffgaff, EE and Three each offering their own Sim-only plans.

However, this type of deal isn't right for everyone. So read on to find out more about Sim-only deals to see if there's one that's best for you.

What are Sim-only deals?

With a Sim-only deal, you'll still get an allowance of calls, texts and data, but the monthly cost will be lower than it would be with a regular pay-monthly mobile contract. This is because you're paying just for a new Sim-card, rather than paying off the cost of a new phone.

Some Sim-only contracts, such as O2's Simplicity, tie you down for only around 30 days at a time. To find out what O2's customers think of it, take a look at our O2 Mobile review

Giffgaff is another provider with its own selection of Sim-only deals, the cheapest of which costs around £5 and includes more than 100 UK minutes and 500 UK texts.

What are the advantages of Sim-only deals?

With a Sim-only deal, network operators or retailers don't subsidise the cost of a handset as they do with many other PAYG and monthly mobile phone deals. Generally, this means you'll get cheaper voice, text and internet services, and cheaper inclusive bundles.

If you don't like the sound of being tied down to a lengthy contract, a Sim-only plan could be the way to go. If you're waiting for a new smartphone to be released, a Sim-only deal can be a quick, easy and versatile option to keep you going until your desired handset hits the market.

A typical Sim-only contract has a minimum term of just 30 days, so you won't have to suffer for long if you end up dealing with poor reception. If you do find that your signal's suffering, you can find out which networks provide the best coverage in your area - see our mobile phone coverage map.

What are the downsides of Sim-only deals?

The most obvious drawback to buying a Sim-only deal is that you'll have to provide your own phone. It can be hard to find Sim-free phones and they can be surprisingly expensive, even more so than PAYG versions.

Even if you already own a phone, you may have to pay to get it unlocked if you want to switch your network operator.

If you're looking for a new handset, make sure you get one that excels in our tough lab tests. Check out our Best Buy mobile phones.

What else do I need to consider?

When looking for a Sim-only deal, make sure the tariff you choose will cover your usage and a little bit extra, otherwise you may end up paying a lot for those extra minutes and texts.

Also, remember to keep an eye on what other Sim-only deals are on offer. Tariffs change all the time and you can easily switch operators.