BEFORE A DEVICE LEAVES HOME

Delete is not
the same as gone.

Our phones hold more personal and financial data than ever.

The National Cyber Security Centre says simply deleting files is often not enough to stop data being recovered. Before you sell, donate or trade in a device, prepare it properly and use its built-in full reset.

Reset before you pass it on

Check your device

An old smartphone and a closed laptop side by side on a tidy wooden desk, ready to be passed on — AI-generated image, not a photograph of a real person or place.

Back it up
Sign it out
Reset it fully
Then reuse or recycle

THE SHORT ANSWER

Prepare, then
reset fully.

A factory reset is the right tool for most people.
The preparation is what stops you being locked out afterwards.

THE RESET

Use the built-in erase

The NCSC says the best way to make sure your data is erased is the device's Erase all content and settings or Factory reset feature. Don't choose any option to keep your files.

Check your device

MORE THAN PHONES

Smart TVs and trackers too

Smart TVs, fitness trackers, speakers and games consoles also hold personal information. Check the maker's website for how to reset them.

What holds data

GETTING READY

Don't lock yourself out

Before you reset, back up, note your logins, and move sign-in codes and smart-home control to another device, then check they work.

The four steps

A QUICK DEVICE CHECK

Where is it
going next?

Pick what is happening to the device to see what NCSC guidance suggests. The bar shows how much of your personal data could go with it.

Device check

Choose a situationSelling or trading it inGiving it to familyLost or stolenSending it for repairJust bought second-hand

Selling or trading it inFull reset

Back up first, then use Factory reset or Erase all content and settings. Don't pick any option to keep your personal files.

Giving it to familyFull reset

The NCSC lists giving a device to a family member or friend as a reason to wipe it, just as for selling.

Lost or stolenRemote erase

There may be options to erase a lost or stolen device remotely, so your data is removed even though you no longer have it.

Sending it for repairConsider a wipe

Returning a device to the manufacturer for repair or replacement is one of the situations in which the NCSC says you may need to wipe it.

Just bought second-handReset before use

Reset it to remove the previous owner's data, then switch on automatic updates and a screen lock when prompted.

Sources: NCSC, Buying, selling and donating second-hand devices; NCSC Device security guidance, Erasing devices.

Based on NCSC guidance for buying, selling and erasing devices.

TWO NUMBERS WORTH KNOWING

Reuse beats
the drawer.

A wiped device can be reused or recycled.
These figures show why that matters.

62 million tonnes

Electronic waste produced worldwide in 2022

Up 82 percent from 2010, according to the UN's Global E-waste Monitor 2024, and on track to reach 82 million tonnes by 2030.

E-WASTE · UN 2024

22.3%

Share documented as properly collected and recycled

Less than a quarter of 2022's e-waste was documented as properly recycled, leaving an estimated US$62 billion of recoverable resources unaccounted for.

RECYCLING · UN 2024

The monitor defines e-waste as any discarded product with a plug or battery, and lists limited repair options and shorter product life cycles among the reasons the gap is growing.

FOUR STEPS BEFORE YOU RESET

Get ready,
then wipe.

The NCSC's checklist for selling or giving away a phone or tablet.

Back up what you want to keep
The reset removes messages, contacts, photos, browsing history, Wi-Fi codes, passwords and apps.
Know your logins
If apps keep you signed in to banking, shopping, email or social media, make sure you know each account's login and password first.
Move codes and controls
If the device receives sign-in codes or controls smart cameras or thermostats, set that up on another device and check it works.
Reset, and don't keep files
Use the full erase or factory reset. If offered the option to keep personal files, don't take it.

Hands holding a smartphone with a blank, softly glowing screen over a desk — AI-generated image, not a photograph of a real person or place.

A small pile of old phones, tablets and chargers in a cardboard box on a wooden floor — AI-generated image, not a photograph of a real person or place.

WHAT HOLDS DATA

Storage hides
in odd places.

NCSC guidance says practically every electronic item now contains some form of storage, from laptops and phones to routers, monitors and memory cards. It notes cases where several gigabytes of sensitive documents were recovered from decommissioned photocopiers and printers.

A factory reset will prevent almost everyone from recovering your data, but the NCSC says a determined expert with specialist tools may still recover some. For data that must never be recovered, it points to its guidance on secure sanitisation, some methods of which destroy the device.

Questions

Questions people ask

Is deleting my files enough before selling a phone?

No. The NCSC says that because of the way storage works, simply deleting files is often not enough to stop data being recovered. Use the device's full erase or factory reset instead.

What does a factory reset remove?

The NCSC says it removes your personal data, including messages, contacts, photographs, browsing history, Wi-Fi codes, passwords and installed apps.

What should I do before resetting?

Back up what you want to keep, make sure you know the logins for accounts the device keeps you signed in to, and move any sign-in codes or smart-home controls to another device.

Should I reset a second-hand phone I've just bought?

Yes. The NCSC suggests erasing it before use to remove the previous owner's data, then switching on automatic updates and a screen lock.

Can wiped data ever be recovered?

Possibly, by a determined expert with specialist tools. For data that must never be recovered, the NCSC points to its secure sanitisation guidance.

Delete is not
the same as gone.