HMRC should increase the rewards it pays out to whistleblowers in line with the US system, according to law firm RPC.
The tax authority paid out over £509,000 to individuals providing evidence about tax fraud over the past year, RPC's research found.
That figure is up from £495,000 in 2021/22 and a 75% increase from the £290,000 paid five years ago, the law firm added.
However, it is just 1.7% of the sum paid to informants by the US Internal Revenue Service (IRS).
The IRS pays whistleblowers 15-30% of the additional tax collected through investigations instigated as a consequence of information received. In 2022, $37.8 million was paid by the IRS to 132 whistleblowers - 58 times the amount paid to UK whistleblowers.
Adam Craggs, Partner and Head of RPC's Tax, Financial Crime and Regulatory team, said:
'More individuals, with evidence of serious tax fraud, would come forward if they knew they could be in line for a life-changing amount of money.
'Paying a proportionate amount for high quality information that helps secure criminal convictions and the recovery of substantial amounts for the Exchequer would be a sensible step. HMRC has been making payments for information on an ad hoc basis for many years and would benefit from improving the system and placing it on a more formal basis.'
Internet link: RPC website