A study by Uswitch found that a fifth (19%) of people say they are holding onto old devices due to concerns over personal data, and one in six (17%) for sentimental reasons.

The price comparison site is encouraging people to recycle their gadgets – and earn money at the same time. It estimated that Brits have 35 million old mobile phones stashed away which would be worth more than £1bn if sold or traded-in.

Uswitch is supporting the Recycle Your Electricals campaign, which is calling on UK households to stop throwing away or hoarding electrical gadgets.

Uswitch found that the average household has seven unused gadgets, with almost one in three (28%) hanging onto old laptops, and a similar proportion (27%) storing out-of-date TVs and digital cameras (27%). More than three million are still holding onto old brick-style phones popular in the early to mid-90s.

The site’s research found that the nation’s unwanted laptops are worth an estimated £2bn, while spare televisions could fetch £900m, digital cameras £2bn, and DVD players £133m.

Nearly two fifths (39%) of consumers say they are holding on to the unwanted tech in case it becomes useful in the future, while almost a quarter (23%) are too lazy to throw it out. About eight million people (19%) say that they haven’t got rid of old gadgets because they are worried about personal data stored on them.

Uswitch found that auction sites like eBay are often the best place to sell old tech. By using eBay, consumers would receive an average of £285 for a pre-owned but fully working iPhone X, whereas using an online marketplace like MusicMagpie yields £220.

According to Uswitch, trading-in an old device with a mobile network provider resulted in some of the poorest returns, with Three offering only £162 for the same handset.

In general, Apple handsets hold their value best. The average resale value for a once top of the range iPhone dropped only 38% over the course of a year. At the other end of the scale, the popular Samsung A5 fell by 71% in 12 months.

Uswitch is urging consumers to consider donating their old mobile phones to Recycle Your Electricals, which ensures that the valuable metals in each phone are reused. The organisation also helps you locate your nearest recycling centre to dispose of your unwanted electronics.

Ru Bhikha, telecoms expert at Uswitch.com, said: “Millions of us are hoarding old, unwanted tech that could be worth a small fortune to its owner, or recycled to reuse the precious metals inside.

“Mobile phones, laptops, games consoles, cameras and TVs all hold a lot of value and can be exchanged for cash with minimal effort. Many of us have a habit for upgrading our phone and holding onto our old one in case they become useful at a later date. They often end up collecting dust when they could benefit somebody else or help reduce the impact of waste on the environment.”

Scott Butler, executive director of Material Focus, the organisation behind the Recycle Your Electricals campaign, said: “Discarded electricals are one of the fastest-growing sources of waste. Many everyday electricals such as mobile phones, TVs, laptops, and baby monitors contain small amounts of precious metals that can be extracted and given new life if they are recycled.

“Recycling your old tech is not only good for the environment, but there is also a huge amount of value in unwanted electricals – whether you sell them so that they can be reused, donated so that someone else in need can benefit, or recycled.

“If you’re having a clear-out, remember that anything with a plug, battery or cable can be recycled. You can find your nearest recycling or donation drop off point by visiting the recycle your electricals website.”