Kensington calculated that UK households spend on average over £4,000 each year on a network of up to 15 self-employed people.
Households are typically spending £626 on lawyers and £235 on cleaners each year with this workforce collectively costing UK households around £107.6bn each year.
Kensington says this trend looks set to continue as the faster pace of life makes society ever more reliant on those offering these services, who in turn are seeking a more flexible way to work.
The bank said the findings highlight the importance of decorators, beauticians, plumbers, electricians, gardeners and cleaners in keeping the wheels of the UK economy moving and partly explain why this element of the workforce has doubled in 40 years.
According to the Office of National Statistics (ONS), out of the 4.6m people registered as self-employed between April-June 2014, 36% or 1.7m have been self-employed since 2009.
However, Kensington said this sector is not well served by the financial services industry. It says that after 18 months of consecutive house price rises in London and the South-East of England, many self-employed people could be forced to move further away from the markets they are trying to serve.
Keith Street, head of Kensington, said: “Self-employed people are overlooked as key workers. Whilst they may not perform crucial life-saving roles, they are essential to the smooth-running of many households across the UK from accounting to cleaning or child care.”
He added: “But they are being squeezed by a rapidly rising housing market and many mainstream lenders that use rigid automated systems to make their decisions.”
