Background
Per Wimmer, a Danish national who lived in the United Kingdom, and his partnership Wimmer Financial LLP faced a series of discovery assessments and closure notices from HMRC covering tax years 2007–08 to 2020–21 and totalling over £1.1 million in combined liability. HMRC’s enquiries examined Mr Wimmer’s personal income across multiple streams — including UK income, dividends, foreign income, rents, and gains — and reallocated partnership profits previously shared with a corporate member entirely to Mr Wimmer personally for later years.
Both applicants sought to appeal those assessments to the First-tier Tribunal (FTT) but did so between 96 and 292 days outside the statutory 30-day time limit. The FTT, applying the three-stage framework from Martland v HMRC [2018] UKUT 178 (TCC), found the delays serious and significant, rejected the suggestion that a June 2023 letter constituted a protected appeal, and held that adviser failures, financial pressures, and focus on settlement negotiations did not amount to a good reason for the delay. Balancing all the circumstances, the FTT refused permission to bring the late appeals. The applicants sought permission to appeal that refusal to the Upper Tribunal; permission was refused on the papers in March 2026 and the applicants renewed their application orally.
Mr Wimmer represented himself and his LLP at the oral renewal hearing on 17 April 2026, concentrating his arguments on the alleged strength of the underlying merits — principally the non-domicile remittance basis issue and a claim of double taxation — and on the severity of the prejudice he would suffer, including the risk of bankruptcy and loss of FCA regulatory authorisation, if permission were withheld.
The Court’s Holding
Upper Tribunal Judge Swami Raghavan refused permission to appeal. On the non-domicile point, the Tribunal held that the remittance basis is not automatic: after April 2008 it applies only where the statutory conditions under sections 809B or 809D of the Income Tax Act 2007 are satisfied, either by a valid claim or by meeting the threshold requirements for automatic application. Because Mr Wimmer had neither made valid claims in the relevant years nor satisfied those conditions, the arising basis applied by default. The Tribunal further noted that the non-domicile argument had not been advanced before the FTT with sufficient legal specificity to require it to treat the merits as overwhelmingly strong.
On the double taxation argument, the Tribunal found that the partnership profit adjustments were substitutive — reallocating income from one taxpayer to another — rather than duplicative. There was no evidence in the FTT’s findings that the corporate member had been taxed on profits once they were reallocated to Mr Wimmer, so no “200% tax” position was established. On time limits, the Tribunal noted that extended discovery assessment periods of up to 20 years are available where loss of tax is attributable to deliberate conduct, and the mere longevity of the assessments did not render them invalid or disclose an arguable error of law.
On prejudice, the Tribunal accepted that refusal of a late appeal carries serious financial and potentially regulatory consequences for Mr Wimmer, but held that such consequences are a common feature of substantial tax disputes and do not of themselves outweigh compliance with statutory time limits or the public interest in finality. Since the delays were long, unexplained, and the merits were not obviously strong, the FTT’s discretionary refusal was well within the generous ambit afforded to a first-instance tribunal. None of the six grounds of appeal disclosed an arguable error of law.
Key Takeaways
- The non-domicile remittance basis is not a default entitlement: from April 2008 onwards, a taxpayer must satisfy specific statutory conditions (a valid claim under s.809B ITA 2007 or automatic application under s.809D) or the arising basis applies as a matter of law.
- Under the Martland framework, the merits of an underlying appeal affect the balancing exercise only where the case is obviously strong or obviously weak; a dispute requiring detailed factual investigation does not tip the scales materially in the appellant’s favour.
- Serious personal consequences — including risk of bankruptcy or loss of professional regulatory authorisation — do not automatically override the public interest in finality when delays in appealing are both long and poorly explained.
- An appellate tribunal will not interfere with a discretionary case-management decision unless it is so plainly wrong as to fall outside the generous ambit of the discretion entrusted to the first-instance judge.
- Extended 20-year discovery assessment time limits may apply where HMRC attributes a loss of tax to deliberate conduct; the mere age of an assessment does not make it invalid on its face.
Why It Matters
This decision reinforces the strict approach UK tribunals take to late appeals in tax proceedings. It confirms that taxpayers cannot rely on the severity of potential consequences — however grave, including professional ruin — to overcome a failure to comply with statutory time limits without a good explanation for the delay. The ruling also provides a clear restatement of the conditions that must be met to access the remittance basis, a point of practical importance for internationally mobile individuals who may assume non-domicile status alone confers a broad exemption from UK tax on foreign income.
For advisers, the case illustrates that merits arguments advanced on a permission application must be legally developed and year-specific: general assertions about unfairness or reference to procedural history will not suffice to demonstrate that a case is overwhelmingly strong. It also signals that claims of double taxation require concrete identification of the years and statutory mechanism by which the same income was brought into charge twice, not merely a comparison of headline assessment figures against reported entity profits.