Should I Unlock My Phone Before Selling It

Every quote on SellMyPhone.co.uk lets you choose "Locked" or "Unlocked". An unlocked device can take any UK or overseas SIM, which usually makes it slightly easier for recyclers to find a new buyer. In 2025 the price gap is often small – but on newer iPhones and flagship Androids it's still worth checking. The quickest way to judge is simply search for your phone on our homepage and check the price difference.

Since December 2021, Ofcom has prohibited UK networks from selling new phones that are locked. That means every brand-new handset bought after that date should already be unlocked straight out of the box.

However, millions of older phones — and plenty of second-hand bargains — were activated before the rule change and may still be locked. The good news is that networks now unlock legacy devices free of charge, usually in a couple of days and often instantly. Unlocking therefore remains one of the quickest ways to add value before you click 'Sell'.

The guidance below sets out how to check your phone's status, how each major network approaches unlocking in 2025 and when it's worth going through the process before sending your device to us.

How Do I Tell If My Phone is Network Locked?

The quickest check is to pop in a SIM from a different network and see if you can make a call. Signal bars and a successful call mean you're unlocked; an error such as "SIM Not Supported" or "Network Locked" means the handset is still restricted.

You can also:

• Open your settings (iPhone: Settings → General → About → Network/Carrier Lock; Android: Settings → Connections → Mobile Networks → Network Operators).
• Contact your provider's live-chat or call centre with your IMEI (*#06#).

Any brand-new UK phone bought since December 2021 should be unlocked by default. If yours isn't, ask your network to refresh its records — it should cost nothing and usually updates within minutes.

What If My Mobile Phone is From Another Provider?

The UK has four physical networks — EE, O2, Three and Vodafone — but dozens of brands ride on top of them. In our trade-in dropdown we list the most common names you'll see on a phone box or bill. The table below shows which underlying network each runs on in 2025. If your phone carries any of these brands, the unlocking rules of the host network apply.

* Legacy Virgin SIMs that still connect to EE follow EE's policy but can also be migrated to O2 free of charge.

Unlocking Phones

Unlocking (sometimes called "SIM unlocking") is completely legal and, since Ofcom's December 2021 ruling, UK networks are no longer allowed to sell new locked devices. For older handsets, each network now offers a straightforward, cost-free route to unlock. The process will not wipe your data and rarely affects your warranty.

Best practice: always try your network first — it's free, safe and provides a paper trail for the next owner. High-street shops and DIY codes still exist but are generally only worth considering for obscure imported models.

1. Through the mobile network

If your handset predates 2021 or was bought second-hand it may still be tied to its original network. To remove the lock you'll need your 15-digit IMEI (*#06#) and a few account details. Submit the request through the network's website, app or customer-service line. All of the providers below process requests free of charge; most iPhones and recent Android models unlock within minutes, while a handful of older devices can take up to 10 days.

EE (inc. Orange & T-Mobile)

All new EE, Orange and T-Mobile handsets sold since December 2021 are supplied unlocked. For older devices, EE will unlock them free of charge. Submit a request online, in the My EE app or by texting UNLOCK to 150. Most iPhones and recent Android phones unlock within 72 hours; very old models may take up to 10 days.

O2

O2 has shipped unlocked phones since 2018 and now unlocks any earlier device for free. Make the request in the My O2 app or by calling 202. Unlocks usually complete the same day — often within minutes once you insert a non-O2 SIM.

Three

Every Three phone sold after December 2013 is already unlocked. If you own an earlier model, call Three on 333 (or 0333 338 1001) with the IMEI and they'll unlock it free of charge — normally inside seven days.

Vodafone

Vodafone stopped selling locked phones in 2022. Legacy devices can be unlocked for free via the online form or by calling 191. Completion is usually within 48 hours, although older feature phones can take up to 10 days.

Giffgaff

Every phone bought from Giffgaff arrives unlocked — no further action required.

Lyca Mobile

Lyca Mobile mainly sells SIM-only plans but any handsets it has supplied are unlocked by default. If you come across a pre-2021 Lyca device that is still locked, contact customer services and they'll arrange a free unlock through their wholesale partner.

ID Mobile

ID Mobile devices are shipped unlocked with the exception of a handful of older iPhones which self-unlock after six months. If yours is still locked, request a free unlock in the iD app or call 7777; turnaround is usually 3-5 days.

Sky Mobile

All Sky Mobile phones are sold unlocked. If your handset appears locked, contact Sky on 0330 041 2639 and they'll refresh the status free of charge.

Tesco Mobile

Tesco Mobile began shipping unlocked handsets in late 2022. Older PAYG and contract phones can be unlocked free once the SIM has been active for 12 weeks. Request the code in your account portal or by calling 4422. Codes normally arrive within seven days.

Virgin Mobile

Virgin Mobile completed its merger with O2 in 2023 and now follows O2's unlocking policy: all new devices are unlocked; any remaining locked handsets can be unlocked free of charge via 789 or the Virgin Mobile app, generally within 72 hours.

* Early iPhones sold by iD Mobile self-unlock after six months or can be unlocked on request.

2. At a high street phone shop

High-street repair shops will still unlock most handsets for around £15, but because the networks now do it free it's usually smarter — and safer — to go through the provider unless you have an imported model they can't support.

3. By yourself

If you have some technological know-how you can also DIY a network unlock. There are a number of tutorials online for doing so. Search out one specific to your make and model of your phone.

But be wary of embarking on this route if you're not confident in your technologies abilities. It's easy to accidentally mess up the software of your device, meaning you'll then have to classify your formerly working phone as broken or faulty, reducing its value.

Is It Worth Unlocking My Phone Before Selling It?

Unlocking is free, but it still takes a little time. Before you request it you can see on our site how much your phone is worth– simply search for your device then use the Network selector to quickly compare prices for "Unlocked" or your network i.e. Vodafone. If the difference is only a few pounds you may prefer to skip the wait and sell it as-is. If the uplift comfortably beats the short delay, go ahead and unlock.

Very old, broken or low-value handsets (typically worth under £30) rarely gain much from unlocking, so it's usually fine to leave them locked.

For everything else, compare the two prices first, then decide – that way you maximise cash without wasting time.