Her Majesty's Revenue and Customs (HMRC) plans to create 30 taskforces to tackle tax evasion by the end of 2012/13.
One of the taskforces, already established and focusing on the South East region, expects to recover around £2.5m, HMRC said.
Another taskforce focusing on property transactions in London launched in December, and that will bring in about £7m, it added.
An initiative to tackle fraudulent tax repayments in London will bring in a further £4.5m, with three cases in this area already under criminal investigation, HMRC said.
Other taskforces already launched will focus on the restaurant trade in London and Scotland, and landlords and construction in the North West.
New forces to be launched this year will tackle tax evasion in the rag trade, motor business and indoor and outdoor markets.
The total 30 taskforces are expected to recover £50m in tax, HMRC said.
HMRC's director of local compliance, Richard Summersgill, said: "Taskforces only target people who are at high risk of breaking the rules and do not pay the tax they owe.
"We know we are going after the right people; some taskforces have hit rates of 100 per cent so far.
"Only those who choose to break the rules, or deliberately evade the tax they should be paying, will be targeted."
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