UK homeowners have an average of £2,813 worth of clutter sitting in their attics.
New research from the Co-operative Bank and the Co-operative Insurance, which saw 2,000 consumers questioned about the contents of their loft, discovered people are undervaluing the so-called junk they have.
Individuals typically think they have around £559 worth of items.
Among the products that commonly feature in attics are TVs, stereos, game consoles, crockery and books.
James Hillon, Head of Home and Family at the Co-operative Bank, said: "At a time when many people are struggling financially, it is surprising to see how much earning potential those items that are rarely seen or used could have."
He added parting with a few sentimental items could give families who are feeling the pinch a much-needed cash boost.
Old computer equipment (39 per cent) was the most common product to be stashed in the attic, while 30 per cent had clothes and ten per cent put their wedding dress in the loft.