A used device carries two kinds of risk for a reseller. One is privacy: photos, messages, saved passwords and payment cards that belonged to someone else, or to you. The other is usability: a phone or tablet still locked to a previous owner's account may be impossible for your buyer to set up. Both are solved by the same habit, done at two points: when you buy, and before you ship. This manual pulls together the steps the major platform makers publish. Software changes often, so follow the current instructions linked below for the exact model and version.
At intake: check for account locks before you pay
Apple's support page on selling an iPhone or iPad explains that when a device is erased with Erase All Content and Settings, Find My and Activation Lock turn off. Its steps include signing out of the Apple Account first, and the page notes that turning off Find My may require the account password. If a seller cannot do that, the device may stay tied to their account.
Google's factory reset page for Android asks you to be sure you know a Google Account on the phone and its password before resetting, and explains that entering security information after a reset shows that you or someone you trust did the reset.
The practical rule for buying used devices:
- Ask the seller to sign out of their accounts and erase the device in front of you.
- If they cannot or will not, treat the device as parts-only at best, and price it that way, or pass.
- Never buy a device the seller cannot unlock. Besides being unusable, it may not be theirs to sell.
Phones and tablets: the erase sequence
For an iPhone or iPad, Apple's page lists, among other steps: back up, unpair an Apple Watch, sign out of iCloud and the stores, deregister iMessage if switching to a non-Apple phone, then go to Settings, General, Transfer or Reset, and tap Erase All Content and Settings. For devices with an eSIM, Apple says to choose the option to erase the device and the eSIM profile.
For Android, Google's page explains that a factory reset erases all data from the phone, recommends charging to at least 70 percent and connecting to a network, and says most phones can be reset from the Settings app. It recommends checking the manufacturer's support site for device-specific steps.
If the device is your own and you are selling it, do these steps yourself. If it is stock you bought, confirm the result.
Computers
Microsoft's "Reset your PC" page explains the Windows reset options, including choices about keeping or removing personal files. For resale, choose the option that removes everything, and follow any prompts about cleaning the drive. Sign out of and remove the Microsoft account and any device-finding features first. Mac computers have their own erase process in Apple's support documentation; search Apple Support for the model and macOS version.
Before you pack: confirm the reset worked
- Power the device on.
- It should show the first setup screen, with no previous owner's name, apps, photos or messages.
- On phones and tablets, check that it does not ask for a previous owner's account during setup. Do not complete setup with your own account unless you plan to erase again.
- Remove SIM cards, memory cards, and any eSIM profile as the maker describes.
- Check cases, sleeves and box inserts for stray cards, receipts or notes.
Photograph the setup screen. It is useful evidence if a buyer later says the device was locked.
What not to promise
Say "factory reset to setup screen" if that is what you did and verified. Avoid claims like "all data destroyed" or "military-grade wipe" that you cannot prove. If you used a specific tool or process, name it plainly.
Devices you cannot wipe
If a device will not power on, you cannot verify a reset. List it honestly as not working or for parts, and say you could not erase it. If the device contains a drive you can remove, some sellers remove and keep or destroy it and sell the rest without storage; say so clearly in the listing.
Shipping after the wipe
Used devices with lithium batteries must go by ground with specific markings under USPS rules. The shipping used electronics manual covers that. Bring the shipping cost and the time spent erasing to the profit bench; devices that take an hour to clear and test need margin to match.
Your own data
The same checklist protects you when you sell your own devices. Back up first, sign out everywhere, erase, and verify. Then remove the device from your list of trusted devices, which Apple's page lists as the last step.
I bought a used phone that is still signed in to someone else's account. Can I just reset it?
Often not. Apple says Find My and Activation Lock turn off when the owner erases the device the right way, and Google's reset page asks for the account details on the phone. A device still tied to a previous owner's account may be unusable for your buyer. Ask the seller to sign out and erase it in front of you, or pass.