SIM-Free Phones UK: Buying a Phone Without a Contract

What a SIM-free phone is

A SIM-free phone is a handset sold without a SIM card and without being tied to a particular mobile network. The buyer chooses a SIM separately, either as a pay as you go SIM or as a SIM-only plan, and the handset works with any provider that uses compatible network technology. This separates two costs that a bundled contract combines: the price of the device and the price of calls, texts and data.

Since 17 December 2021 mobile companies in the UK have been banned from selling handsets locked to their network. That means a phone bought from a network is not restricted to that network, and a phone bought elsewhere can be used with any provider. In practice the main difference between buying SIM-free and buying from a network is how the cost is structured, not whether the handset will work on another network.

Buying SIM-free usually means paying for the handset upfront or through a separate finance agreement, then paying a monthly amount for the SIM-only plan. Because the two are separate, the monthly SIM cost can be changed or cancelled without affecting ownership of the phone. The handset remains the buyer's property once paid for, and it can be kept, sold or passed on when a new phone is bought.

SIM-free plus SIM-only versus a handset contract

Pay monthly contracts with a phone usually run 12, 18 or 24 months and can cost more in the long term than buying a phone separately plus a SIM-only deal. The bundled price covers both the handset and the airtime, and the total is spread across the contract term. SIM-only deals are usually cheaper than contracts that come with a phone, and their terms are one month rolling, 12 months or 24 months. A shorter term gives more flexibility, while a longer term can lower the monthly price.

The comparison is not simply the monthly figure. A bundled contract can show a lower monthly payment than a SIM-free phone bought upfront plus a SIM-only plan, because the handset cost is spread over the term. Over the full term, however, the bundled contract can cost more. Ofcom estimated customers with a bundled handset contract could save an average of £75 a year by moving to SIM-only when the deal ends. That figure applies at the point the deal ends, when the handset portion of the bill is no longer justified by a new device.

For a buyer who keeps a handset for several years, the SIM-free route separates the device cost from the ongoing airtime cost. Once the handset is paid for, only the SIM-only plan remains, and that plan can be changed to match actual usage. For a buyer who wants a new handset regularly and prefers a single monthly payment, a bundled contract spreads the cost but ties the airtime to the same provider for the term.

End of contract: why bills can stay high

When a pay monthly contract with a phone reaches its end date, the handset portion of the bill has effectively been paid off, but the provider does not automatically reduce the monthly charge. The customer continues to pay the same amount for airtime alone unless they take action. This is why bills can stay high after the minimum term ends, even though the device is no longer being financed.

Rules introduced by Ofcom give customers information at that point. Since 15 February 2020 providers must warn customers between 10 and 40 days before a contract ends, with the end date, current and future prices and their best deals. Out-of-contract customers must be told every year about their provider's best deals. These messages are designed to prompt a review, either by moving to a SIM-only plan with the same provider or by switching to another provider.

The saving identified by Ofcom, an average of £75 a year for bundled handset customers moving to SIM-only when the deal ends, comes from removing the handset element from the monthly bill. A customer who stays on the same out-of-contract deal keeps paying for a phone that is already paid for. Reviewing the plan at the end date, or when the annual out-of-contract message arrives, is the point at which the monthly cost can be brought back in line with actual usage.

Unlocked phones and switching networks

Because handsets can no longer be sold locked to a network, switching between providers is simpler than it was before 17 December 2021. A phone bought from one network can be used with another network's SIM, provided the handset supports the frequencies and technologies the new provider uses. A SIM-free handset bought from a retailer or manufacturer works in the same way.

To keep a mobile number when switching, text PAC to 65075. The PAC is valid for 30 days and is given free of charge. To switch without keeping the number, text STAC to 75075. The new provider must complete the switch within one working day. The customer does not need to contact the old provider to cancel, because the switching process handles that.

Before switching, it is worth checking the coverage and the plan terms of the new provider, including the contract length and any price rises written into the terms. Ofcom advice includes avoiding unlimited data unless it is needed, checking fair usage limits, using Wi-Fi and Wi-Fi Calling, and asking for a bill limit. These steps apply whether the handset is SIM-free or bought from a network, and they help keep the monthly cost predictable after the switch.

Refurbished and older models

Refurbished and older handsets are a common way to reduce the upfront cost of going SIM-free. A refurbished phone is a previously used device that has been checked, repaired where necessary and resold. The condition and warranty vary by seller, so the terms should be read before purchase. An older model that is still supported by the manufacturer can also be bought new or used, often at a lower price than the current model.

The main considerations are battery condition, software support and compatibility with the networks being considered. A handset that no longer receives security updates may still work, but it will not receive fixes for newly discovered issues. A handset with a worn battery may need a replacement, which adds to the total cost. Compatibility matters because a phone must support the frequencies used by the chosen provider.

Pairing a refurbished or older handset with a SIM-only plan keeps the two costs separate in the same way as a new SIM-free phone. The handset cost is lower, and the monthly plan can be matched to usage. Because the handset is not tied to a network, it can be moved between providers by using a PAC or STAC, and the switch must be completed within one working day.

Checklist before buying SIM-free

Before buying a SIM-free phone, check the handset supports the frequencies and technologies used by the intended provider, and confirm the software support period. Check the total cost of the handset plus the SIM-only plan over the period the phone is expected to be kept, and compare that with the total cost of a bundled contract over its term. Check the SIM-only plan length, which may be one month rolling, 12 months or 24 months, and check any price rise terms written into the plan.

For the plan itself, Ofcom advice is to avoid unlimited data unless it is needed, check fair usage limits, use Wi-Fi and Wi-Fi Calling, and ask for a bill limit. These steps reduce the risk of unexpected charges. If the plan is replacing an out-of-contract bundled deal, the provider must have warned between 10 and 40 days before the contract ends, and out-of-contract customers must be told every year about the provider's best deals, so those messages can be used as a prompt to compare.

If switching provider, text PAC to 65075 to keep the number or STAC to 75075 to switch without keeping it. The new provider must complete the switch within one working day. Keep a record of the end date of any existing contract and the notice period, and check the final bill after the switch to confirm no further charges apply. Buying SIM-free and using a SIM-only plan separates the handset from the airtime, which makes each part easier to review and change.

Source: Ofcom.

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Frequently asked questions

Is a SIM-free phone the same as an unlocked phone?

A SIM-free phone is sold without a SIM and is not tied to a network. Since 17 December 2021 mobile companies in the UK have been banned from selling handsets locked to their network, so a phone bought from a network is also unlocked. In practice both can be used with any compatible provider's SIM.

How much can be saved by moving to SIM-only at the end of a contract?

Ofcom estimated customers with a bundled handset contract could save an average of £75 a year by moving to SIM-only when the deal ends. The saving comes from removing the handset element from the monthly bill once the device has effectively been paid off.

What warning must a provider give before a contract ends?

Since 15 February 2020 providers must warn customers between 10 and 40 days before a contract ends, with the end date, current and future prices and their best deals. Out-of-contract customers must be told every year about their provider's best deals.

How is a mobile number kept when switching networks?

Text PAC to 65075 to keep the number, or STAC to 75075 to switch without keeping it. The PAC is valid for 30 days and is free. The new provider must complete the switch within one working day.

What should be checked before choosing a SIM-only plan?

Ofcom advice is to avoid unlimited data unless it is needed, check fair usage limits, use Wi-Fi and Wi-Fi Calling, and ask for a bill limit. It is also worth checking the plan length, which may be one month rolling, 12 months or 24 months, and any price rise terms.