What to do with your smartphone before selling it: 6 steps

Before selling, exchanging or handing over your smartphone to someone else, first back up any data you need to keep, then unlink your accounts, and only then completely wipe the device using the system’s factory reset function.

The order is important: if you start by manually deleting photos and contacts, synchronisation may also delete them from the cloud; if you reset a secured Android device without properly signing out of your account, the new owner may be prompted to verify the previous account. These instructions were verified on 14 September 2026 using reference materials from Apple, Google and Samsung.

Details

In short: back up your data → ensure the transfer is complete → unlink associated devices and accounts → remove the SIM/eSIM and memory card → perform a standard full factory reset → check that the phone boots up as a new device.

These steps are intended for personal iPhones and Android smartphones that the owner can manage themselves. Corporate phones with organisation profiles, devices with forgotten passwords, or damaged devices may require a separate procedure from the manufacturer, mobile network operator or administrator.

1. Back up anything you want to keep

Save your photos, contacts, messages, files and any other important data before carrying out any data-wiping procedures. Apple explicitly states that backing up is the first step before selling an iPhone or iPad. Google warns that a factory reset deletes data from an Android phone, and after this, you can only restore what has been saved to your account or by other means.

Don’t assume that having a cloud account means everything has been backed up: data from individual apps may be stored differently. Before proceeding, open your backup or set up your new device and check a few categories of data that are critical to you.

2. Complete the transfer to your new phone before wiping your old one

If you already have a new smartphone, first transfer your data to it and check the result. For iPhones, Apple recommends Quick Start on compatible versions of iOS; for Android, the transfer method depends on the manufacturer and the operating system version.

Pay particular attention to items that are difficult to recover once you’ve lost access: authentication apps, local notes and files, and messaging history, if it isn’t synchronised automatically. There is no universal transfer method that is guaranteed to copy data from every third-party app.

3. Unlink accounts and associated devices

On your iPhone, sign out of your Apple ID following the instructions for your version of iOS, and unpair your Apple Watch if it was paired with your phone. Apple also recommends removing your old device from the list of trusted devices after wiping it. If you’re switching from an iPhone to a phone from another manufacturer, make sure to disable iMessage registration separately.

On Android, before handing over the device, remove your Google Account from it: Google states that this disables the device’s security, which, following an unauthorised factory reset, requires the previous account or a screen lock. On Samsung phones, the company also asks you to log out of your Samsung Account before a trade-in. Menu item names vary depending on the user interface, so please refer to the manufacturer’s instructions for your specific model.

4. Deal with the SIM, eSIM and memory card

Remove the physical SIM card and any removable memory card before handing over the phone. If you’re using an eSIM, check that your number has been transferred to the new device and delete the profile from your old phone as part of the wipe process.

For iPhones, Apple explicitly states that if a prompt appears when erasing a device with an eSIM, you must delete both the device and the eSIM profile when selling it. On Android, the interface and procedure for managing eSIMs depend on the manufacturer and network operator, so do not delete an active profile before transferring your number if you still need it.

5. Perform a full factory reset using the system’s built-in function

After backing up your data and unlinking your accounts, use the system’s built-in command to completely erase all data. On an iPhone, this is ‘Transfer or Reset [device]’ → ‘Erase All Content and Settings’. Apple states that this wipe removes personal data from the device and disables Find My and Activation Lock.

On Android, use the factory reset option in the phone’s settings and refer to the manufacturer’s instructions. Google warns that a factory reset erases data and apps; if the device is locked, you may be asked for a PIN, screen password or Google Account details. A reset using buttons via recovery mode is not a convenient alternative to properly unlinking an account: security measures following such a reset may require your previous login details.

6. After the reset, check the initial set-up screen

Switch on the phone after the reset and ensure that it reaches the initial setup screen as a new device, rather than opening your apps, photos or account. Do not go through the initial setup again using your own account — the buyer must do this themselves.

If the device asks for the previous Apple ID or Google Account to activate it, do not hand it over to the buyer in this state: the owner’s lock has not been fully removed. Refer back to the official instructions for the relevant platform and complete the unlink process.

Why this is important

Manually deleting individual files is a poor strategy before selling. Apple specifically warns that if the user is signed in to iCloud, manually deleted contacts, calendars, documents or photos may disappear from iCloud servers and other connected devices. A systematic process involving backup, signing out of the account and a full wipe minimises this risk.

There is also the reverse problem: the phone may be wiped clean but unsuitable for the new owner due to Activation Lock on Apple devices or Android’s post-reset security measures. Therefore, the practical criterion for readiness is not simply an empty gallery, but a setup screen that does not prompt for your previous login details.

For corporate devices, phones managed by MDM, devices with forgotten passwords, and cases where the smartphone has already been handed over to someone else, this procedure should not be applied mechanically: follow the specific procedure provided by the manufacturer, organisation or mobile network operator.

Source

Verified on 14 September 2026. Main sources: Apple’s guide on preparing an iPhone or iPad for sale, transfer or trade-in; Google’s guide on securing Android after a factory reset; Google’s guide on performing a factory reset on Android; Samsung’s guide on preparing a device for trade-in.