The taxman said it would mine its computer systems for anomalies, pinpointing people who have “failed to pay the right tax”.
It said that there would also be scrutiny of the ability to hide second incomes from private maths tutors as well as fitness and dance coaches.
Businesses using trading platforms like eBay and Gumtree will be examined as will tradesmen willing to work without charging VAT for their services.
HMRC said a similar campaign last year against doctors and dentists had raised around £10m, including one single payment of £1m in unpaid tax and fines. Two earlier amnesties for offshore accounts generated £500m.
Mike Wells from HMRC said: “We will use the information we gather to pursue people who choose not to use the opportunities we provide for them to put their affairs in order on the best possible terms. It will be more expensive if we come and find people, so I urge them to come forward and disclose voluntarily.”
The campaigns will see people offered a partial amnesty, with any penalty capped at between 10pc and 20pc of the tax outstanding over the last five years.
However, those that fail to act face fines of between 35 per cent and 100 per cent of the tax evaded.
John Cassidy, tax investigation partner at accountants PKF, said: “Traders who have been less than honest should seriously consider getting in touch with HMRC and making a voluntary disclosure before they get a knock on the door.”