PUK code: how to unlock your SIM after a wrong PIN
A PUK (PIN Unblocking Key) is an eight-digit code that unlocks a SIM card after three wrong PIN attempts. It lets you set a new PIN.
In plain words
A PIN is like the key to your school locker. Try the wrong key three times and the locker jams. The PUK is like the caretaker's master key that opens the locker and lets you fit a new lock. But the master key only works a few times: ten mistakes and the locker has to be replaced.
How it works
- After three wrong PINs, the phone asks for the PUK.
- You enter the eight-digit PUK, then a new PIN.
- The SIM unlocks with the new PIN.
- After 10 wrong PUK attempts, the SIM is locked permanently.
- A locked SIM can be replaced by your operator and you keep your number.
Where you'll see it
The PUK is printed on the plastic card you popped the SIM out of, or it is in your operator's online account or app. You can also get it from customer support after confirming your identity.
Does it matter when buying
Keep your PUK somewhere safe in advance. And never guess it at random - after 10 mistakes the SIM must be replaced. Scammers sometimes ask you to read out your PUK - do not do it.
Myths
- Myth: You can guess the PUK. Reality: After 10 attempts the SIM is locked for good.
- Myth: Without the PUK your number is lost. Reality: Your operator can replace the SIM and keep your number.
FAQ
Where do I get my PUK?
On the SIM packaging, in your online account or from your operator's support team.
Does the PUK change?
Usually not; it is fixed for the SIM card.
Does an eSIM have a PUK?
Yes, your operator can give it to you.