Don’t give away your personal data when you sell your phone

You can potentially make hundreds of pounds by selling an old phone, tablet or laptop. But you could be giving away sensitive data in the process unless you wipe the device properly.

We sent Android and iOS smartphones and tablets, along with PC laptops and Apple Macbooks, to specialist data-recovery lab Kroll Ontrack, to see what data had been left on them.

Although we found that most devices were clear, some had not been properly wiped and still had emails, photos, text messages and documents left on them. Ensure you don’t get caught out with our guide.

Smartphone reviews – from the iPhone to the Galaxy, and beyond

Sell an old phone – make £££

Apple tech holds its value best, but other gadgets, even from a few years ago, can still be worth something. We’ve crunched some numbers based on selling fully working devices with all the original accessories.

For example, an Apple iPhone 6 (16GB) now fetches an average resale price of £224. That’s 32% off an iPhone 7 (32GB). A MacBook Air 13-inch (2014) resells for £243 on average. That’s 26% off the latest comparable MacBook Air (1.6GHz, 128GB, £949).

It’s not just Apple tech, either. A Samsung Galaxy S5 (16GB unlocked) resells for a rather paltry £82, but that’s still 16% off a Galaxy S7 (32GB). An HP Envy 15 2014 (i7 4th gen) goes for £155 on average, which is 22% off the latest comparable HP Envy 15.

Black Friday, sales, bargains, get a good deal

How to wipe an old device

All the personal data we did find in our test was down to owners not wiping their devices properly. Follow the steps below to ensure your emails, photos, text messages and more are deleted permanently.

Android devices: Go to your device’s settings, click Backup & reset, followed by Factory data reset. Then tap Reset phone or Reset device. Find out more about wiping Android devices in our in-depth guide.

Apple iPads & iPhones: If you use iCloud on your device, sign out. Then use the iTunes restore function, or select Erase All Content and Settings from the menu. Both of these options delete the encryption key associated with the device, rendering any remaining data unrecoverable. Learn more in our guide to wiping an old iPhone or iPad.

PC laptop: Windows enables a quick sanitisation of your hard drive. But using free third-party software, such as Disk Doctors Data Sanitizer or Killdisk, will fully overwrite the data. To ensure that sensitive data is gone, they offer extra data-overwriting services costing around £40. Get the full lowdown in wiping data from a hard drive.

Apple Macbook: Restart in recovery mode (hold down Cmd+R during restart). Use Disk Utility to erase the hard drive by selecting the main volume, and click Unmount then Erase. When you’ve done that, re-install MacOS.

Sell your old phone – your rights

Resellers, such as Amazon Marketplace and eBay, generally won’t accept any responsibility for the removal of data. Instead, the onus is on you to ensure you fully wipe your device of all data before you hand it over.

You don’t want someone snooping on your personal photos, emails or messages from a device you’ve sold. Although it’s unlikely that a criminal would use it to cause you financial harm, it’s worth following the above steps so you can sell with peace of mind.

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One reply

  1. If you can spare the cash, why not donate your old phone to charity? I recently gave my old phone to Oxfam. I’d had it wiped, but I’m assured that Oxfam will check it again before it goes to its new owner.

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