How to Erase Your iPhone or Android Before Selling It (So the Buyer Gets Nothing)

You've got a new phone. The old one is sitting in a drawer, or you've already listed it for sale. Before it leaves your hands, there's one thing you can't skip: wiping it completely.

Not just deleting your photos. Not just signing out of an app or two. A proper, full erase, done in the right order, so the next person gets a clean device and nothing else.

Here's exactly how to do it, for both iPhone and Android.

Why a simple delete isn't enough

Most people assume deleting their files before selling is sufficient. It isn't.

When you delete a file, the phone usually marks that space as free rather than erasing the contents. A University of Cambridge study of Android factory resets tested used phones running Android 2.2 to 4.3 and found that flawed resets left data recoverable, including Google account credentials on every phone with a flawed reset. Those phones are old, and current phones handle this differently, but the lesson holds: the way you erase a phone matters.

A proper factory reset on a current phone changes the picture. iPhones and most current Android phones encrypt the data on the device, and a reset erases the encryption keys, which leaves what remains unreadable. But the order of steps matters, and a few easy-to-miss details, like Activation Lock on iPhones or Factory Reset Protection on Android, can trip up both you and the buyer.

Before you do anything: back up your data

Both iPhone and Android have built-in backup.

On iPhone: Go to Settings > [your name] > iCloud > iCloud Backup > Back Up Now. You can also back up to a Mac or PC through Finder or iTunes. A computer backup covers almost all of your data, but only an encrypted one includes Health data and saved passwords.

On Android: Go to Settings > Google > All services > Backup and make sure backup is on. Tap "Back up now" to trigger a fresh backup before wiping.

Either way, double-check that your photos, contacts, and any app data you care about are safely stored before you move on. Once you erase, there's no recovering anything from the device itself.

How to erase an iPhone before selling it

The steps below apply to any iPhone running iOS 15 or later. Do them in this order. Apple's guidance on selling or trading in an iPhone covers the same ground.

Step 1: Sign out of your Apple ID

This is the most critical step. When Find My is active, your iPhone is tied to your Apple ID through Activation Lock. A buyer can't set the phone up as their own until that lock is cleared. Sign out first, and it clears automatically.

Go to Settings > [your name] > Sign Out at the bottom. Enter your Apple ID password when prompted. Choose to keep a copy of any data on the device if you want (it doesn't matter since you're erasing next), then tap Sign Out.

Once you're signed out, Find My turns off and Activation Lock is gone. The device is no longer linked to your account.

Before you sign out, unpair any Apple Watch that is paired with the phone and remove the phone from your trusted devices list, as Apple's guidance describes. If you are switching to an Android phone, also turn off iMessage and FaceTime in Settings so your texts reach the new phone.

Step 2: Handle your eSIM

Many iPhones use an eSIM. iPhone 14 and later models sold in the US have no SIM tray, and the iPhone Air is eSIM-only everywhere, as Apple's list of eSIM-only models explains. In many other countries, models up to the iPhone 16 still have a SIM tray.

If your phone uses an eSIM, go to Settings > Cellular and delete it (if you have more than one plan, tap the plan first, then choose Delete Plan). Contact your carrier to cancel or transfer your service, and set up the new phone with a new eSIM from them, as Apple's eSIM guidance describes. You can also let the erase in the next step handle it: iOS will ask whether to erase the eSIM too, so choose the option that erases it.

If you have a physical SIM card, just pop it out.

Step 3: Erase all content and settings

Go to Settings > General > Transfer or Reset iPhone > Erase All Content and Settings. Confirm when prompted. The phone will erase itself and reboot to the "Hello" setup screen, the same screen it showed the day it left the factory.

If Find My is still on when you run this step, iOS may ask for your Apple Account password before it erases the phone, as Apple notes. Signing out first (Step 1) keeps the sequence simple and means the phone is no longer linked to your account.

How to erase an Android phone before selling it

Android's process has a couple of extra steps compared to iPhone, mostly around removing your accounts first. Google says to remove your Google Account before you reset or hand over the phone. If you don't, Factory Reset Protection (FRP) stays active, and the buyer will be asked to sign in with the last Google account used on the device.

Step 1: Back up, then remove your Google account

If you haven't backed up yet, do it now (Settings > Google > All services > Backup > Back up now).

Then remove your Google account from the device. Go to Settings > Accounts (or Passwords & Accounts on some models) and tap your Google account. Choose Remove Account. This disables Factory Reset Protection before the wipe.

On a Samsung phone, also remove your Samsung account (Settings > Accounts and backup > Manage accounts > your Samsung account > Remove account) and any other linked accounts, as Samsung advises.

Step 2: Remove your SIM card and any memory cards

Pop out your physical SIM. If your phone has a microSD card, remove that too. Samsung notes that a factory reset does not erase an SD card, so anything on it stays there unless you remove or format it separately.

Step 3: Factory reset

The path varies slightly by manufacturer:

• Google Pixel: Settings > System > Reset options > Erase all data (factory reset)
• Samsung Galaxy: Settings > General Management > Reset > Factory data reset

Confirm the action, enter your PIN or password if prompted, and follow the on-screen instructions. The phone will restart and return to its out-of-the-box state.

Encryption is what makes a reset effective. Phones that launched with Android 10 or later must use file-based encryption, so a reset that erases the keys leaves the data unreadable. Many earlier phones are encrypted too, but older phones, and some that were upgraded from older versions, may not be, so a proper reset matters even more on those.

What you should check before handing it over

Once the reset is complete, do a quick check before boxing it up:

• Power it on. Confirm it shows the setup screen (Hello on iPhone, the Android welcome screen on Android). If it boots straight into a home screen, something went wrong.
• Confirm Activation Lock / FRP is off. On iPhone, the "Hello" screen means the phone is ready to set up, while an "iPhone Locked to Owner" screen or a request for the previous owner's Apple Account means it is still linked, as Apple explains. On Android, setup shouldn't ask for the previous Google account.
• Check your account's device list. Make sure the old phone no longer appears in your Apple Account or Google Account devices. If it does, remove it.

If everything looks right, the buyer is getting a clean device.

One more thing worth thinking about

Selling your phone is a good reminder that your personal data is constantly moving across devices, apps, accounts, and browsers, and a lot of it you never think about until something goes wrong.

Wiping your old phone handles what's on the hardware. But your accounts, passwords, and email live well beyond the device itself. A clean factory reset won't fix anything that was already exposed, for example in a data breach.

Once the phone is gone, remove it from your account's device list and consider changing the passwords of any important accounts you're worried about. If you're not sure whether your information has already been exposed, it's a good time to check your email address and phone number against known breaches.

Conclusion

Erasing a phone properly comes down to a few steps in the right order: back up, sign out of your accounts, remove the SIM and any memory card, and run the factory reset. Then check that the phone is ready for its new owner.

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