Is the phone carrier locked? How to check before you buy
Updated November 3, 2026
A carrier-locked phone only works with SIM cards from the carrier that sold it. That can be fine if you're on the same carrier. If you're not, the phone won't connect with your SIM until that carrier removes the lock, and that's something the seller usually has to arrange, not you.
On an iPhone: look in Settings
Open Settings > General > About and find Carrier Lock. Apple says that if it reads "No SIM restrictions", the iPhone isn't locked to a carrier. If a carrier name or anything else appears, it's locked.
You can also check from the IMEI before you meet, so you don't drive across town for a phone that won't work with your plan.
On an Android phone: test with your SIM
There isn't one setting that shows carrier lock on every Android phone. The reliable test is to put in your own SIM, restart, and make a call and load a web page on mobile data. If it asks for a code or shows no service with your SIM, treat it as locked.
Why phones are locked
Carriers lock many of the phones they sell, for example while the phone is being paid off. Each carrier has its own rules for removing a lock. Only the carrier can remove it, so a seller who says "it's easy, you can call them" is asking you to take on their problem.
If it's locked
- Locked to your own carrier: it may work for you, but check with your carrier before you pay.
- Locked to a different carrier: ask the seller to get the lock removed first, then check again.
- Locked and the seller won't say which carrier: walk away.
Check the phone before you pay
One $1.99 report checks the lost/stolen list, iCloud (Find My), carrier lock and Samsung Knox Guard, with one plain answer. No account needed.
Check a phone for $1.99See a sample report