Millions of mobile phone owners could each receive £180 just by selling old devices, money guru Martin Lewis said.
The journalist, who presents The Money Show Live on ITV, said it's bad for the planet to dispose old mobile handsets in the bin.
Instead, selling your old phone could boost your bank balance by as much as £180.
Speaking on his programme on Thursday, Martin, 49, said: “If you’ve got an old mobile handset do not throw it away as it is terrible for the environment - batteries, lead, beryllium, flame retardants could all cause environmental harm if you chuck it away and it goes into landfill.”
There are numerous online websites designed to help sell phones and other electronic gadgets, Daily Record reports.

Martin, who often also appears on This Morning, added: "Get yourself on to a comparison site like sellmymobile.com and compareandrecycle.co.uk and see if you can flog it.
"Relatively, not that new iPhones and Samsung's can be worth up to £180.
"I’d also check eBay as well, if you’re on it, because you might be able to sell it for more there but these are the easiest ways to do it."
The price you get offered will depend on the age of your phone and the condition it’s in.
But the financial guru did issue a warning before you go digging through your drawers:
“Not much protection with these sites though so do check reviews and once you send it to them they might say'there’s a scratch on it so we’re not giving you as much', but still, it’s far better than binning it," the journalist, who grew up in Manchester, added.

Chemicals in batteries, like those used for mobile phones, are harmful to the environment.
Beryllium is used in them as a structural support and a heat sink. It is an extremely toxic element though.
But most mobile networks have ways old phones can be recycled if they need upgrading. They often offer customers cash in return for this.
You can still recycle even if you’ve had your new handset for a while.
Just go to the website where you got your mobile phone and search for recycling options.