How do SIM free phones work?

For most of us, a mobile is more necessity than luxury, but that doesn’t mean you should pay more than you need to. Here, we take a look at SIM free phones and how they work so that you can decide whether it’s an option that’s right for you.

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What is a SIM free phone?

SIM free phones are exactly as they sound – they’re phones that don’t come with a SIM card. In most cases this means the phone isn’t tied to a particular network, so you’ll be able to buy a separate SIM from any provider and use it with your handset.

How does a SIM free phone work?

When you buy a SIM free phone, you’ll need to insert the SIM card yourself – this could be an existing SIM card or a new SIM from a new provider.

So long as the handset is unlocked, putting in your SIM should activate the phone and you’ll be able to use it there and then.

If you’ve got an older handset, it’s a good idea to check what type of SIM card will fit. Newer phones use smaller cards (either a nano SIM or micro SIM) whereas previous models used standard SIM cards.

What does it mean if a phone is ‘locked’

Locked phones are tied to a particular network (for example, O2 or Vodafone) and cannot be used with anyone else. If you want to keep the handset but switch to another network provider, you’ll need to unlock your phone before you can use it with a new SIM card.

The good news is that since December 2021, phone companies have been banned from selling locked handsets. However, it’s worth noting that if you’re buying a second-hand phone, especially from a private seller, it might be SIM free, but it could still be ‘locked’ to a particular network.

How do I unlock my phone?

Unlocking your phone is now easy and free if you’ve met any minimum contract terms. In most cases, all you need to do is contact your phone provider and ask them to unlock your phone.

You can also do this by texting ‘PAC’ to 65075 (it doesn’t matter which provider you’re with). Your provider will then reply with a switching code to unlock your phone.

Is SIM free the same as pay-as-you-go?

SIM free and pay-as-you-go (PAYG) aren’t the same. SIM free refers to the handset – in other words, it’s a phone that comes without a SIM. PAYG refers to how you buy airtime (the term that describes your data, calls and texts).

With that in mind, you can buy a PAYG SIM card and put it in your SIM free phone. A PAYG deal would mean you only pay for the data, minutes and texts you use. If you’re a very light mobile phone user, choosing a PAYG deal could be the cheapest way to own a phone. The drawback is that you’ll need to remember to ‘top up’ if you’re running low on airtime. It can also work out more expensive per minute, text or gigabyte (GB) of data. Read more about picking the best plan for you here.

How do I choose a SIM card for my handset?

If PAYG isn’t the right option for you, you can consider buying a SIM-only plan. These deals bundle together airtime usually for 30-days at a time (instead of PAYG where you buy airtime when you need it).

There’s a wide range of SIM-only plans on the market. Some come completely contract free so you can buy a one-month plan and then switch to another deal after that. You can also buy SIM deals as monthly rolling contracts or as fixed-term agreements (usually for 12-months). In most cases, you’ll pay less if you commit to a fixed contract, but this will usually mean you’ll be subject to a credit check.

What’s the alternative to a SIM-only deal and PAYG?

If you need a new handset and airtime, a pay-monthly plan may suit you better. As well as your data, calls and texts, these packages include a brand-new handset. Plus, with incentives and discounts, pay-monthly plans can sometimes work out cheaper than buying a SIM free phone and separate SIM.

You’ll need to bear in mind that because pay-monthly deals are a type of credit, the phone provider will carry out a credit check against you. If you do sign up for a contract plan, you’ll also need to be mindful about paying bills on time. If you don’t, you could face penalties. If you consistently miss payments, it could affect your credit rating which could in turn impact your ability to get credit in the future.

What are the benefits of buying a SIM free phone?

When it comes to buying a new phone, there’s a lot to consider, so here’s a quick summary of the reasons why you might want to buy a SIM free phone:

  • Can be used with any network provider.
  • Easy to switch so you can always be on the best plan for your needs.
  • Potential for greater choice of phone as you can buy directly from the manufacturer.

On the flip side, one of the biggest drawbacks is that buying a SIM free phone and a separate SIM might not always give you the best deal. To help ensure you do find a deal that suits your needs, remember to compare all types of airtime.


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