The research found that 11.7 m out of 24.7m homes in the UK either have inadequate cover for their home contents and belongings or no cover at all.
Howard Posner, managing director of Halifax General Insurance, said: "It is really easy for people to underestimate the value of their home contents. That is why it is important to have the safety net of contents insurance."
"But not all insurance policies offer the same level of cover. Halifax contents insurance is one of the few policies with an unlimited sum insured which means no policyholder is underinsured should the unexpected or worst happen."
