That estimate has come from The City UK, the representative body for financial services and related professions.
It said the tax total was roughly equivalent to total UK spending on the police.
The report Total Tax Contribution Study for UK legal and accounting activities found the sector collectively generated employment of 693,000 and 23% of EU employees in the sector were in the UK.
Miles Celic, chief executive of The City UK, said: “The legal and accounting sector make a considerable contribution to the UK economy in their own right, and are an essential part of the world-leading financial and professional services ecosystem.
“The UK is the leading global hub for legal and accounting expertise and it is vital that we not only preserve that, but we continue to grow it.”
He said expertise extended from the City of London to other major financial centres such Manchester, Bristol and Edinburgh, and across the country there were nearly 60,500 legal and accounting businesses, and those with fewer than 99 employees made up 99% of that total.