Three UK unlock policy in 2026, for the UK shop holding the phone

Three is the easy one. It gave up SIM locking in 2014, nearly eight years before Ofcom made the rest of the market follow, so a Three handset that is actually locked is a rare and old thing. This page records what Three says about its own policy, what the Ofcom rule changed for everyone else, and the small set of Three devices that can still ask for a code.

Last reviewed 2026-10-28. Written for shops by STACKS. Not affiliated with any carrier.

Three stopped locking in 2014

Three's own blog states it plainly: "we stopped selling any locked phones as of 1 January 2014" (source). For anyone with an older Three phone, the same post says to visit a Three store and "get it unlocked for free" (source). The post dates from May 2017 and Three has not published a newer consumer policy page that could be read on 2026-10-28; the support article Three's own search returns sits on support.three.co.uk, which answered with an error and a certificate that does not match its hostname. The one line indexed from it is that the personal details on the unlock form should match the account owner's details on the bill (source)). That line is unverified against a readable page.

Third party guidance fills the gaps with care. 3g.co.uk's guide, updated July 2024, says "if you bought your device from Three after January 1st 2014 then it will already be unlocked", that for anything earlier "chances are it's locked", that the online form "no longer seems to be present", and that the route is to call 333 from a Three phone or 0333 338 1001 from any other phone (source). The same guide says you need a Three account before contacting Three, and that a Three SIM is free online (source). Three publishes no processing time; unverified.

The Ofcom rule since December 2021

Ofcom's ban on selling locked handsets came into force on 17 December 2021, with a 24 month cap on bundled handset contracts in the same package (source). When Ofcom announced it in October 2020, Three was named with O2, Sky and Virgin as already selling only unlocked phones, while EE, BT, Vodafone and Tesco Mobile were given a year to switch; Ofcom put the typical unlock cost at "around GBP 10" and said about half of people who tried had difficulties (source). Ofcom's own page returned 403 to fetches on 2026-10-28, so it is cited through press (source). For Three the rule changed nothing in practice; it is relevant here because a shop seeing a locked phone with a Three SIM in it is almost certainly looking at another network's lock.

The devices that can still be locked

Two groups remain. First, handsets sold by Three before 1 January 2014, now at least twelve years old and of little trade-in value. Second, mobile broadband hardware. In Three's community, a moderator said the Huawei MiFi "should be unlocked", while other users reported Huawei and ZTE routers asking for a network unlock code and a moderator acknowledged that "some of our previous Huawei range are network locked", directing them to customer services (source). The quick test the community suggests is the universal one: put another network's SIM in and see whether it connects or asks for a code (source).

For an old iPhone on iOS 7 or later, 3g.co.uk notes the unlock completes by restoring the device through iTunes, which wipes it (source). Back up first.

How to check lock status

Three's own advice is to "ask the network directly or try a different network SIM and make a call to see if it works" (source). On an iPhone, Settings > General > About > Carrier Lock shows "No SIM restrictions" when there is none. On recent Samsung phones, Settings > Connections > More connection settings > Network lock status. A Three branded phone that fails these tests was most likely locked by whoever sold it before it reached Three's network, and that network's page on this site is the one to read.

The trade-in case

A genuinely locked Three handset is a pre-2014 device, and Three's route to unlock it is a store visit or a call matched to the account owner's details on the bill. A shop holding it with no account holder has no clean route, though the device's age usually makes the point academic. The more common case is a phone on a Three SIM whose lock belongs to EE, Vodafone or an overseas carrier. The value gap between locked and unlocked stock is covered on locked vs unlocked value, and the financed and blacklisted page explains the free check for a device whose original owner stopped paying, because a barred IMEI stays barred on every UK network whether or not the SIM lock is gone.

Our Three services are listed near the top of this page as STACKS sells them: each row states the condition it applies, the turnaround and whether it is refundable if it fails. A network unlock does nothing for Activation Lock; Apple's guidance is not to take a used iPhone that still asks for the previous owner's Apple Account (source).

If it is your own phone

Visit a Three store or call 333; Three says it is free (source). Unlock STACKS serves approved businesses. See how approval works.

Questions shops ask

RELATED EE (UK) O2 / Tesco (UK) Vodafone (UK) All carriers Locked vs unlocked value Financed and blacklisted

APPLY FOR AN ACCOUNTWHATSAPP