Pensioners on a Keighley council estate have been warned to take extra care when visited by gas and electricity sales teams.
Braithwaite People's Association is urging elderly residents to ensure they do not switch suppliers unless they really want to.
The warning comes after a 69-year-old man unwittingly signed a new contract during a visit by two sales girls.
John Philip, of West Bank Rise, believed he was signing-up for a survey to show whether he would save money by transferring.
He had allowed the women to examine his meter and fill in a document, which he signed. He later realised it was a contract.
Mr Philip says: "I was really annoyed when I realised what I had done.
"I think people should be warned, older people especially.
"They said I could save money, but they didn't say how much. I assumed they were going to work it out."
Mr Philip's son, also called John, the treasurer of Braithwaite People's Association, has issued a warning. The association is checking whether pensioners who attend its popular bingo sessions have signed contracts without realising.
Mr Philip Jr says: "If people get a visit from these companies, they should not sign anything until they've been given figures and have agreed to transfer their electric or gas."
Mr Philip suggests concerned pensioners either talk to a younger relative, or contact the BPA helpdesk any Wednesday morning at the Keith Thompson Community Centre (phone 610200).
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