Ian Mihill v The Commissioners for HMRC

Permission to appeal to the Upper Tribunal requires a realistic prospect of showing a material error of law. Under section 49 of the Taxes Management Act 1970, HMRC must accept late notice when Conditions A to C are met. Whether HMRC considered reasonable excuse must be assessed in the context of the correspondence, and HMRC may take account of missing information it had requested.

In reviewing a decision on late appeals, the FTT may give significant weight to statutory time limits. Appellate tribunals should be slow to interfere with the FTT’s balancing of relevant factors. The seriousness and significance of delay are distinct matters. None of the grounds raised an arguable material error of law, so permission was refused.

Ian Mihill sought permission to appeal against the First-tier Tribunal’s refusal to allow late appeals against tax assessments and penalties totalling £875,623, excluding interest. The FTT found that the decisions had been notified to him and applied the guidance in Martland v HMRC [2018] UKUT 0178 (TC).

After the FTT refused permission to appeal, the Upper Tribunal refused Mr Mihill’s renewed application on the papers. He then applied for reconsideration at a hearing. He argued that HMRC had not properly considered the statutory conditions for accepting late notice, that the FTT had misapplied or should have departed from the late appeal guidance, and that it had failed to consider separately the seriousness and significance of the delays. The central question was whether any ground disclosed an arguable error of law material to the FTT’s decision.

1. Disposition. Following reconsideration, permission to appeal was refused. None of the three grounds showed an arguable error of law material to the FTT’s decision.
2. HMRC’s consideration of late notice. Section 49(3) of the Taxes Management Act 1970 requires HMRC to agree to late notice where Conditions A to C are met. Condition A was met, but HMRC was not satisfied that there was a reasonable excuse under Condition B. The letter refusing the late appeals had imperfect wording, but it had to be read in the context of the earlier correspondence. HMRC had asked for further details of illness and bereavement and was entitled to take account of the absence of further information. It was therefore not arguable that HMRC had assumed there was no reasonable excuse or had failed to consider the statutory conditions. The judicial review point had not been pursued before the FTT; in any event, given the conclusion on Condition B, it was not arguable that the FTT erred by not addressing it expressly.
3. Late appeal guidance and balancing. The Court of Appeal had concluded that the guidance in Martland v HMRC [2018] UKUT 0178 (TC), as amplified by HMRC v Katib [2019] UKUT 189 (TCC), was appropriate. The FTT could give significant weight to statutory time limits, and appellate tribunals should be slow to interfere with the weight it assigned to the factors. The suggested reasons for departing from the guidance—including the amount at stake, correspondence history, different delay periods, finality and HMRC’s conduct—did not make it arguable that the FTT had erred. The FTT had considered the different delays and the merits of the separate decisions; the seriousness of the delays had been conceded.
4. Seriousness and significance. At the first stage of the Martland approach, the FTT had identified the length of delay and whether it was serious and significant as separate matters. Since seriousness was conceded, it had to determine significance. It did so, and no arguable error arose from not analysing the conceded point further.

• Upper Tribunal (Tax and Chancery Chamber). After a hearing on 18 June 2026, reconsidered its paper refusal of 6 February 2026 and again refused permission to appeal on all grounds.
• First-tier Tribunal (Tax Chamber). Refused permission to appeal on 16 October 2025. Its decision of 31 July 2025 (reference TC/2024/01251) refused permission for late appeals against the assessments and penalties.