How do I check whether my phone is network unlocked?
Put another network's SIM in it. That is the whole test. If it works, it is unlocked; if it refuses, ask the network that sold it, which will unlock it free.
- Difficulty
- beginner
- Time
- 15 min
- Read
- 3 min
- Safety
- caution
Short answer
Borrow a SIM from someone on a different network and put it in the phone. If it registers and can make a call, the phone is unlocked. If it shows a message about the SIM not being supported or asks for an unlock code, it is locked to the original network. Contact that network — UK networks unlock handsets they sold, free, on request, and it usually takes a day or two.
A network lock is a restriction in the phone's software that only accepts SIMs from one operator. It exists to protect the subsidy on a handset sold cheaply with a contract. UK regulation and industry practice have moved firmly towards unlocked handsets, and most phones sold now are unlocked from the start — but plenty of older handsets, and second-hand ones, are not.
Safety
Step by step
- Do the SIM test.Another network's SIM, in the tray, restart. Working service means unlocked. A message about an unsupported SIM, an invalid SIM, or a request for an unlock code means locked. This takes two minutes and is definitive, which is why every other method is unnecessary.
- Check settings as a secondary indicator.Some phones display a carrier lock status in the mobile or about section of settings. It is convenient when present but not universal, and the SIM test settles it regardless. Do not trust an absent setting as evidence either way.
- Identify who sold the handset.Only the network that supplied it can unlock it, regardless of who you pay now. If you bought it outright from a manufacturer or a general retailer, it was almost certainly never locked. If it came with a contract or as a pay-as-you-go bundle, that network is the one to ask.
- Ask that network, free.Most now handle it through their app or website, and it is free. Some conditions apply — the contract may need to be a certain age or fully paid, or a pay-as-you-go handset may need to have been used for a minimum period. They will tell you the condition rather than refusing outright.
- Have the IMEI ready.The unique handset identifier, shown by dialling star-hash-zero-six-hash, and also in the about section of settings. The network identifies the handset by this. Note it down anyway — it is what you give the police and the network if the phone is stolen.
- Wait, then test again.Unlocking is usually applied within a couple of days and often much sooner. Some phones need a restart or a factory reset to apply it, and the network will say if so. Test with the borrowed SIM again rather than assuming it worked.
- For a second-hand phone, insist the seller handles it.Only the original account holder can request an unlock. If you buy a locked phone, you may be unable to get it unlocked at all, because the network will want the account holder. Test with your own SIM before paying, in person, every time.
- Do not confuse this with activation lock.A network lock restricts which SIM works. An activation lock ties the whole phone to the previous owner's account and makes it unusable by anyone else. A phone that will not get past a sign-in screen has the second problem, and only the previous owner can release it.
Questions people ask
Why would I need it unlocked?
To switch to a cheaper tariff, to use a local SIM abroad, and to sell it — an unlocked phone is worth more and sells faster. Even if you have no plans to change network, unlocking it costs nothing and removes a future obstacle.
Does unlocking void the warranty?
Not when done officially by the network. Paying an unofficial service to modify the phone's software is a different matter and may well affect both the warranty and the phone's security.
Is my phone locked if it only came with one network's apps preinstalled?
Not necessarily — a network-branded handset with the operator's apps may still be sold unlocked. The SIM test is the only reliable check.
What if the network refuses?
Ask why. The usual reasons are an outstanding contract balance, a handset reported lost or stolen, or a minimum usage period not yet met on pay-as-you-go. Each of those has a resolution, and if the phone is reported stolen you have a much bigger problem than a lock.