O2 has issued a message urging all mobile phone users with old, unwanted smartphones to trade them in for a free cash boost of over £200.

Research from the company has found that the average UK household is sitting on more than £218 worth of unwanted mobile phones, yet only one in 10 (11%) Brits have traded in their devices in the last five years.

The firm says nearly 10 million mobile users are unaware their unused devices can actually make them a significant amount of money if they trade it in for recycling instead of just throwing it away.

Leaving old phones to gather dust in drawers at home will see the device depreciate in value meaning you risk missing out on a substantial sum of cash compared to trading in your old phone straight away.

O2 is now urging people to trade in their old devices via O2 Recycle to boost their finances and prevent electronic waste ending up in landfill.

The service is open to anyone – regardless of their mobile operator – and since its launch in 2009, has recycled more than four million devices and paid over £350 million to customers.

Last year alone the programme processed more than 100,000 devices which were saved from landfill by being resold as refurbished devices to customers or recycled.

Regina Mutonono from O2 Recycle advises: “Check how much your tech is worth: O2 Recycle is available to anyone – regardless of their mobile network. You can see how much cash you get from your old tech including phones, tablets, smartwatches, earbuds.

“Don’t let tech collect dust: Sell your unwanted mobile, laptop or tech as soon as you’re done with it. The sooner you sell it, the more money you’re likely to get for it.

“Remove your SIM before trade-in: You should ensure that the SIM is taken out prior to selling the handset – or memory card where applicable, but don’t worry about your personal data being accessible, as O2 Recycle will wipe data from all devices for you.”