The amount of tax HMRC suspects may have been underpaid by big businesses has increased to £24.8bn, a 13% rise on the previous year following a widening of the scope of investigations, according to analysis by law firm Pinsent Masons.

Pinsent Masons says that the amount of tax that HMRC’s large business directorate believes is underpaid also represents a 31% jump on the 2014/15 figure of £18.99bn.

Heather Self, Partner at Pinsent Masons, said “Another £3bn rise in the tax HMRC is querying shows that HMRC is broadening its horizons and putting a far wider range of transactions under scrutiny. We are seeing an increasing number of challenges to arrangements that would previously have been regarded as routine and perfectly acceptable.”

“HMRC is putting the affairs of more and more companies under the microscope as a result, increasing the costs for those businesses. At the same time, many of the largest businesses are struggling with HMRC’s customer relationship manager system and finding it more difficult to get uncertainties resolved in real time.”