Will Mellor told presenters Gamal Fahnbulleh and Mel Barham that he has been left paranoid after being the victim of fraudsters.
The Strictly Come Dancing star says he only grew suspicious when he discovered someone rifling through his post.
The 46-year-old, who is from Stockport, says the scammers stole his identity, a 'substantial' amount of money and said that it had been going on for 'some time'.
Will, who narrowly missed out on the Strictly final in December, claims it is not the first time he has been a victim of fraud as he warned others to be vigilant at all times.
He says it could happen to anyone and says checking bank statements as often as possible is a way to combat the crooks.
Will said: "My neighbour bumped into me and said that she saw someone hanging around my letterbox and thought she saw him take something out of it.
"I put my CCTV facing towards the letterbox to see if I could catch anything and low and behold I caught a guy with his hand in my letterbox taking mail out.
"I found out that he had been intercepting my mail and had opened several accounts in my name.
"He had stolen my identity and had been laundering money through these accounts. One of them had £20,000 in it."
He added: "Nationwide have carried our research that shows there's a lot of people who give too much information online on social media platforms.
"70% of people share personal details on social media. Just be careful what you are posting on your bios. After what happened to me I go through my bank statements daily.
"My wife got me a wallet for Christmas that prevents people from using contactless mechanisms that can steal money off your card just by being close to your wallet.
"It's great because now when I am on the train I am not worried about people being too close to me.
"After I was the victim of identify fraud I became really paranoid."
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