Judgment summary
This is a decision on the reconsideration of an application for permission to appeal to the Upper Tribunal (Tax and Chancery Chamber). Mr Mihill had sought permission to appeal against the FTT's refusal to allow him to make late appeals against various tax assessments and penalties.
The FTT had refused permission for late appeals, applying the guidance in Martland v HMRC [2018] UKUT 0178 (TC) (para 7). The FTT also refused permission to appeal that decision (the FTT PTA Decision, 16 October 2025) (para 1). The Upper Tribunal refused permission on the papers on 6 February 2026 (the UT Papers Decision) (para 2), and Mr Mihill applied for that decision to be reconsidered at a hearing, which took place on 18 June 2026 (para 3).
By the time of the hearing, the Court of Appeal had decided HMRC v Medpro Healthcare Ltd and others [2026] EWCA Civ 14, confirming that the Martland guidance, as amplified by HMRC v Katib [2019] UKUT 189 (TCC), remains appropriate (paras 12, 29). The Supreme Court subsequently refused permission to appeal Medpro CA (para 13).
Following reconsideration of all three grounds, the Upper Tribunal refused permission to appeal (para 39).
Background
Mr Mihill applied to the FTT for permission to make late appeals against various assessments and penalties totalling £875,623 (excluding interest) (para 6). The FTT found that all the decisions had been notified to him and refused permission for late appeals, applying the Martland guidance (para 7).
The FTT released its decision on 31 July 2025 (TC/2024/01251) (para 1). Mr Mihill applied to the FTT for permission to appeal, which was refused on all grounds on 16 October 2025 (the FTT PTA Decision) (para 1). He then renewed his application to the Upper Tribunal on 14 November 2025, which was refused on the papers on 6 February 2026 (the UT Papers Decision) (para 2).
On 18 February 2026 Mr Mihill applied for the UT Papers Decision to be reconsidered at a hearing, held on 18 June 2026 (para 3). Mr Mihill had been represented before the FTT by Jesmin Rahman of Tax Resolute Ltd, and later instructed counsel, Harriet Brown and Rebecca Sheldon, who prepared the permission and reconsideration applications. Mr Mihill was subsequently made bankrupt and could no longer instruct counsel, though Ms Brown and Ms Sheldon attended the reconsideration hearing as amicus curiae (para 3).
Core dispute
Mr Mihill relied on three grounds of appeal against the FTT's refusal of permission to make late appeals (para 9).
Ground 1 was that it was not open to HMRC to refuse to accept a late appeal, and that the FTT erred in failing to consider whether HMRC had correctly, or at all, considered the conditions in s49 Taxes Management Act 1970.
Ground 2 was that the FTT applied the wrong test by following Martland, and erred by giving the Katib factors excessive weight in the balancing exercise, and/or by not departing from that guidance.
Ground 3 was that the FTT erred in failing to consider, at stage 1 of the Martland test, the seriousness and significance of the delay separately, treating them as a single composite requirement.
Court findings
On Ground 1, the Tribunal found that s49(3) TMA 1970 requires HMRC to accept a late appeal where Conditions A to C are met (para 18). Reviewing the correspondence and the FTT's findings of fact, including the letter of 19 May 2021, the Tribunal held it was not arguable that HMRC had failed to consider the conditions, or that if they had, they would have been required to accept a late appeal; HMRC had sought further information about the claimed illnesses and bereavements and was entitled to conclude it was not satisfied for the purposes of Condition B (paras 20-25).
On Ground 2, the Tribunal noted that the Court of Appeal in Medpro CA had confirmed that the Martland guidance, as amplified by Katib, is appropriate (paras 12, 29). It held that the weight given to factors in the balancing exercise is a matter for the FTT, with which appellate tribunals should be slow to interfere, and that none of the matters relied upon by Mr Mihill, including the amount at stake exceeding £800,000, the pattern of HMRC correspondence, the differing lengths of delay, and HMRC's conduct during the enquiries, were arguably good reasons for departing from the guidance (paras 32-33).
On Ground 3, the Tribunal found that the FTT had expressly treated seriousness and significance of the delay as separate issues at FTT[97] and FTT[100], and had gone on to consider whether the agreed-serious delays were also significant, applying Hysaj, concluding at FTT[106] that all delays were serious and significant (paras 36-38). It was not arguable that the FTT had treated these as a single composite requirement.
Outcome
Following reconsideration, the Upper Tribunal refused permission to appeal on all three grounds (paras 26, 34, 38, 39). The decision was issued to the parties on 27 August 2026.
Major issues / areas of contention
- Whether HMRC properly considered Conditions A to C in s49 TMA 1970 before refusing to accept Mr Mihill's late appeals.
- Whether the FTT erred in law by applying the Martland guidance, as amplified by Katib, in refusing permission for late appeals.
- Whether the Court of Appeal decision in Medpro CA confirmed that the Martland/Katib guidance was appropriate.
- Whether the FTT gave excessive weight to certain factors, including the amount at stake and the length of delays, in the balancing exercise.
- Whether the FTT erred in failing to consider separately, at stage 1 of Martland, whether the delay was serious and whether it was significant.