Rectification of tax return to correct charitable donation

In 2017-18 the taxpayer donated £800 000 to a charity he set up in memory of his late wife. He wished to treat the donation as made in 2016-17 for gift aid purposes. However in his 2016-17 tax return which he filed electronically in November 2017 he incorrectly included £400 000 in the charitable giving section when he should have put £800 000. The charity claimed back the tax on the full donation. He submitted an amended return in February 2018 and also emailed HMRC to explain the error.

In November 2018 HMRC opened an enquiry into the return. It concluded that it was not possible for him to carry back the donation because ITA 2007 s 426 requires the whole amount to be claimed in the relevant tax return. The First-tier Tribunal decision in Cameron (TC415) confirmed that an election to carry back relief had to...