Short answer
Activation Lock ties an iPhone to the owner's Apple Account. Only the owner can remove it — in person or remotely at icloud.com/find. Never buy an iPhone that shows 'iPhone Locked to Owner'.
Activation Lock is why stolen iPhones are hard to resell — and why buying one second-hand without checking is risky.
Check before you pay
- Ask the seller to erase the phone in front of you.
- Turn it on: you should see the Hello screen, not 'iPhone Locked to Owner'.
- Insert your SIM and confirm the phone activates.
- Check Settings › General › About for 'Unknown Part' messages.
If the phone is already locked
- Contact the seller — they can remove it at icloud.com/find › All Devices › Remove from account.
- If you can't reach them, Apple only helps with original proof of purchase in your name.
- There's no legitimate 'bypass' service. Sites that promise one are scams or sell stolen phones.
Selling your own iPhone
- Back up.
- Settings › your name › Sign Out (this turns off Find My and Activation Lock).
- Settings › General › Transfer or Reset iPhone › Erase All Content and Settings.
- Remove your SIM or transfer your eSIM.
Sources
Find Next Phone is an independent retailer. Apple, iPhone and iOS are trademarks of Apple Inc. Illustrations are our own and are not Apple product images.