Residents have been warned to be on the alert for letters in the post offering to predict their future for a fee.
Consumer advice officers at East Riding of Yorkshire Council's trading standards service said they had received complaints about scam letters.
Letters from so-called psychics or clairvoyants were one of the most common direct mail scams, they said.
Sometimes letters could be aggressive and suggest something bad would happen if people disregarded them.
They advised people to ignore the letters.
Anyone wanting to reduce the amount of junk mail they receive can register with the mailing preference service.