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What's best: SIM only or pay monthly?

We show you how to choose the right mobile phone contract for you...

Choosing a new phone contract might feel complicated at first.

When deciding between pay-as-you-go, SIM-only and a monthly billed contract, you’ll need to consider your own phone usage and what best suits you.

By making the right choice that fits your needs, you can avoid paying for extra services you don’t need, or being charged for going over your allowance.

Not sure where to start? Don’t worry, we're here to guide you through the different options to help you find the right deal for you.

SIM-only

Check out some of our cheapest SIM-only deals:

  • O2 sim only
    5G
    • 32GB of 5G data
    • Unlimited minutes
    • Unlimited texts
    • download speed limit
    • EU roaming included
    • £8.00 per month
    12 month contract From O2
  • Three sim only
    5G
    • 120GB of 5G data
    • Unlimited minutes
    • Unlimited texts
    • download speed limit
    • £12.00 per month
    24 month contract From Three Mobile
  • VOXI sim only
    5G
    • 90GB of 5G data
    • Unlimited minutes
    • Unlimited texts
    • download speed limit
    • Unlimited social media, music & video
    • £15.00 per month
    1 month contract From VOXI
  • GiffGaff sim only
    5G
    • 25GB of 5G data
    • Unlimited minutes
    • Unlimited texts
    • download speed limit
    • £10.00 per month
    18 month contract From giffgaff
  • Three sim only
    5G
    • 40GB of 5G data
    • Unlimited minutes
    • Unlimited texts
    • download speed limit
    • £10.00 per month
    24 month contract From Three Mobile
  • Lebara Mobile sim only
    5G
    • Exclusive
    • 20GB of 5G data
    • Unlimited minutes
    • Unlimited texts
    • download speed limit
    • Discounted price for 3 months
    • £7.99 per month
    1 month contract From Lebara Mobile

What does SIM-only mean?

As the name suggests, a SIM-only deal comes with just a SIM card. It’s not like a mobile phone contract, where you get a handset along with data, minutes and texts.

It’s a great option if you own your current phone and don’t feel the need to upgrade just yet – you just get a SIM to pop in it.

How do SIM-only deals work?

With a SIM-only contract, you pay a monthly charge to get a fixed amount of calls, texts and data.

Some SIM-only deals operate on a one-month rolling basis, so you’re free to change or cancel your contract every month. It’s a great choice if you don’t want to commit to a long-term contract.

On the other hand, if you do decide to commit to a SIM-only contract (usually for 12 or 18 months), you can get a greater data allowance for the same monthly outlay.

As you don’t get a handset, SIM-only deals are very affordable. Many networks have SIM plans that start from as little as £5 a month, which give you a decent amount of data, and often unlimited minutes and texts.

Many SIM-only deals also don’t require a credit check. So it’s a good option if you have a bad credit score, as you’ll usually need to pass a credit check to get a mobile phone contract.

Pros and cons of SIM-only deals

Pros:

  • Very affordable, with deals starting from £5 a month
  • Flexible – not tied to a long-term contract
  • Simple and straightforward

Cons:

  • You need to have your own handset

Pay-monthly phone contract

What is a pay-monthly phone contract?

With a pay-monthly phone contract, you get a new handset along with a monthly allowance of minutes, texts and data.

Compared to a pay-as-you-go deal, you’ll get a generous amount of data, calls and texts. Plus, many networks like to throw in perks, free gifts and rewards with a phone contract.

If you can’t stomach the cost of buying a handset outright, a pay monthly phone contract is your best bet. It’ll spread that cost over the length of your contract, making it much more manageable to pay off in monthly instalments.

Some providers separate the amount you're paying for the handset and the amount you pay for the package, so the cost will fall once the initial contract is finished.

However, the downside is that you can be locked into a contract that lasts for anything from 12 months to 24 months and sometimes even more. If you're a real new-phone junkie, this may mean routinely paying extra to upgrade early.

Not to mention, you’ll need to pass a credit check, as networks want to make sure you can pay off the handset.

Pros and cons of pay monthly

Pros:

  • Makes mobile phone prices more manageable by spreading the cost over the length of your contract
  • Many networks offer incentives and rewards with pay monthly phone contracts

Cons:

  • Works out as more expensive than if you’d bought a handset outright
  • Requires you to pass a credit check, particularly for the latest and most expensive handsets
  • Less flexibility – you’re usually tied to a 12-month or 24-month contract

Pay-as-you-go

What’s the difference between pay-as-you-go and pay monthly?

Pay-as-you-go can mean different things with different networks. In some cases, it's simply another term for a one-month allowance of data, minutes and texts, which you can choose to buy again when it runs out, or switch to another plan – so, essentially, it's like a SIM-only plan.

In other cases, it means topping up your SIM with a certain amount of credit, and paying money for every call, text and MB of data you use. With this kind of pay-as-you-go deal, you simply pay for the data, minutes and texts you use.

There's no contract, so you don’t need to pay a charge every month – you can choose to top up once you use up your allowance, or leave whenever you like. And you won’t need to pass any credit checks at all.

Some providers even offer great value bundles of data, call time and texts if you upload a certain amount of money each month, letting you use your phone almost like a contract.

The main difference between pay-as-you-go and a pay monthly phone contract is that you don’t get a handset with pay-as-you-go. Instead, you’re simply topping up your existing phone with credit to use.

Is pay-as-you-go cheaper?

It depends on your phone usage and whether you already own a phone.

If you’re happy with your current mobile and aren’t a heavy user, a pay-as-you-go deal may suit you well. You only need to top up whenever your phone credit is running low.

However, the rates you’ll pay for every minute, text and MB of data used will be more expensive than if you get a SIM-only or pay monthly contract – both of which offer ample allowances for the price you pay.

If you use your phone a lot, you’ll likely end up paying more with a pay-as-you-go deal.

Pros and cons of pay-as-you-go

Pros:

  • The most flexible option, with no contract at all
  • No credit check required
  • Good option if you don’t use your phone too much

Cons:

  • Works out as more expensive if you use your phone a lot
  • You need to have your own handset

Compare deals

Find out more about a pay as you go SIM or visit our mobile phone deals page where you can compare contract, pay-as-you-go and SIM-only deals and find the right mobile phone package for you.

You can compare by deal type, cost, handset or even free gift – whatever matters most to you, we'll help you find best deal.

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