This has emerged in new research from Scottish Widows, which also discovered that 81% of people who work for themselves don’t seek financial advice.
Two-thirds of the self-employed are without a regular income, with just one in five receiving a monthly pay packet.
The study also found that almost half of the self-employed see their income fluctuate as a result of owning their own business, with a similar proportion putting this down to being a freelancer, contractor or consultant.
Scottish Widows found that, as the cost of living rises and private rents in the UK increase at the fastest rate in five years, a quarter of those surveyed only had enough money to cover their financial outlays for three months if they were unable to work.
With the research highlighting the group's vulnerability to financial shocks and the importance of expert financial advice, one in three of those surveyed didn't think they could afford professional advice, while one-quarter said they hadn't thought about seeking advice from an independent financial adviser.
Scottish Widows says not being eligible for Statutory Sick Pay can prove a real problem for the self-employed and their financial resilience.
While many have taken steps to secure financial protection for themselves and their families, 13% of people working for themselves in the UK still don't have critical illness cover or life insurance.
Just under a third of them said these forms of protection weren't a financial priority, one in four said they were prepared to risk not being covered, while others said they didn't require these policies or couldn't afford them.
Rose St Louis, protection director at Scottish Widows, said:
"The self-employed don't have the luxury of having an employer to rely on for sickness cover or health insurance, making them extremely vulnerable to loss of income or unexpected financial shocks.
"Advisers have an important role in opening up conversations with clients to ensure that all aspects of protection are discussed, and that the right policies are in place to help create financial peace of mind."
