Nearly a third of family businesses in the UK were started by the grandparents of the current owners, according to new research published ahead of ‘National Grandparents Day’ on Sunday.

The report, created by the Centre for Economics and Business Research for Barclays, also found that more than seven in 10 family firms have been in the family for at least one generation.

It found that second-generation or older businesses were most numerous in construction and agriculture and that combined they contribute more than £100 billion to the UK economy.

Rebecca McNeil, head of business lending and enterprise at Barclays, said business owners should pan succession sooner rather than later, although she admitted this was often a tricky subject to broach for many.

“It’s never too early to put a succession plan in place – it is a topic that people are reluctant to talk about but an important step to make,” she said. “Many family businesses face the challenge of an ever changing business landscape, bringing new systems, technology and changing customer needs. This is where new generations can help to offer a fresh perspective.

She added: “We advise SMEs to seek specialist advice on matters such as financial planning, tax and legal issues to help them put a viable succession plan in place.”

Three-in-five business owners covered by the research said they wanted to pass the business to their children, but 23% of people aged 55 and over worried their children would not want to inherit.

The report also uncovered a third-generation family firm that had banked with Barclays for 92 years.