Difference between calculating a claim and making one

The taxpayer overpaid stamp duty land tax by making a mistake in the way that it calculated multiple dwellings relief. It was common ground that the return contained an error and that the taxpayer had overpaid tax. There was no dispute as to the amount. HMRC accepted that it would be liable to repay the overpaid tax unless the overpayment was by reason of a ‘mistake in a claim’.

The taxpayer claimed a refund of the amount which it had overpaid by submitting a claim for overpayment relief and did this within the relevant time limit.

HMRC refused on the basis that overpayment relief is not available when it arises from a mistake in the making of a claim. The taxpayer disputed this saying there had been a mistake in the calculation of a claim.

The taxpayer said the law made a ‘clear distinction between a...