Practice generally prevailing ended in September 2017

The taxpayers each included top slicing relief (TSR) calculations in their tax returns (Mr J in his 2017-18 return and Mr S in his 2016-17 return) but later claimed overpayment relief on the basis that the TSR calculation methodology was flawed.

HMRC stated that it considered the original TSR calculations were in line with the practice generally prevailing at the time and rejected the taxpayers’ overpayment relief claims.

The taxpayers appealed.

It was common ground that HMRC’s computerised TSR calculations were incorrect in some cases following changes to the income tax legislation from April 2016 in relation to the personal and savings allowances. The issue was from when it could no longer be said that there was a practice generally prevailing.

The taxpayers were represented by Tim Good who provided a wealth of evidence in the form of articles in various publications (including in Taxation) and correspondence...