Facebook and Instagram posts flaunting overseas holidays, private schooling and business-class flights will be used to nab tax cheats as part of a crackdown on dodgy returns that understate income.

The Australian Taxation Office aims to recoup billions of dollars worth of taxes on undeclared income, with the social media evidence used to complement intelligence gleaned through data matching, The Australian reports.

So if your lifestyle doesn’t match the amount you earn on paper, your affairs could be under the microscope.

According to the latest ATO ­annual report, the tax office collected $9.6 billion from “compliance activities last year, more than two-thirds of it for income tax.

It prosecuted more than 1300 individuals and 400 companies for offences ranging from noncompliance with lodgement obligations, to making false or misleading claims and keeping false records.

There were 21 people convicted and sentenced for serious criminal matters, with penalties ranging from four to 87 months and reparation orders forcing taxpayers to pay back about $4.5 million.

“We will continue to use more sources and more sophisticated intelligence to target compliance action on those who warrant such action,” ATO Commissioner Chris Jordan said in the report.