New analysis by IFS has suggested Scotland's tax raid on top earners may have lost Holyrood money.
Scotland decided to raise taxes on high earners more aggressively than Westminster, a decision that the Institute for Fiscal Studies said backfired.
The leading think tank suggested this was on the basis that higher earners left the country or sought loopholes to avoid paying higher taxes.
The decision to squeeze higher earners came after the former SNP leader Nicola Sturgeon capatalised on greater powers on income tax in 2017-18.
David Phillips, an economist at the IFS, said: “Increases in the top rate of tax are unlikely to raise much – with evidence from the first of Scotland’s reforms in 2018–19 suggesting they may even reduce revenue.”
According to the think tank, the analysis should serve as a warning to the Scottish Government ahead of its Budget next month.
Mr Phillips said: “The evidence currently available suggests that if the aim is to raise revenue, the Scottish Government should at least pause any plans for further increases in Scotland’s tax rates on higher incomes.”