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    TaxKilnUK tax guidance
    TaxKilnUK tax guidance

    Tribunals + HMRC Enquiries → Scenarios + anti-charlatan

    12 Tribunal + Enquiry Scenarios + Corridor-Specific Anti-Charlatan Patterns

    Twelve concrete scenarios covering the most-common HMRC enquiry + penalty appeal + voluntary disclosure pathways. Each scenario identifies: the relevant statutory route, the appropriate response sequence, the realistic cost of self-serve action, and the specific signals indicating when specialist counsel via tax chambers becomes warranted (versus when 'specialist' firm engagement is markup over self-serve). Plus eight corridor-specific anti-charlatan patterns with detailed statute-grounded rebuttals — each shows the marketing claim, the underlying statutory reality, and the typical self-serve or appropriately-scoped professional alternative. The themes are consistent: most enquiry responses + penalty appeals are self-serve via established procedural routes; specialist counsel via leading tax chambers (11 New Square / Pump Court Tax Chambers / Devereux Chambers / Old Square Tax Chambers / 15 Old Square) is genuinely warranted for COP9 + substantive law disputes + complex transfer pricing — NOT for routine penalty appeals or basic discovery defences.

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    Guidance, not advice. We explain the rules, we don't assess your situation. Always seek financial or tax advice from your accountant, or contact HMRC. Read our editorial scope →

    In plain English

    Twelve scenarios laying out the real-world enquiry, penalty, and disclosure pathways. Each follows the same structure: facts → identify route → response sequence → cost analysis → when (if ever) specialist counsel is warranted. Scenario 1 — First-time SA late-filing penalty + reasonable excuse template. Tom missed 31 January, has hospital evidence; appeals via Perrin v HMRC [2018] UKUT 156 (TCC) 4-stage framework. Self-serve, £0 cost. See penalty-regime page worked example for full walkthrough. Reference: cross-link /downloads/hmrc-late-filing-appeal template. Scenario 2 — HMRC opens TMA 1970 s.9A enquiry into SA return — week 1 protocol. Acknowledge in writing within 7 days; request specifics of HMRC's concern; preserve all records; assemble contemporaneous documentation. Do NOT engage 'HMRC investigation specialist' on £8,000 retainer for opening response. Qualified accountant if existing relationship; self-serve possible for straightforward cases. Most s.9A enquiries close at this initial stage with no penalty + agreed minor adjustment. Scenario 3 — Discovery assessment received 5 years after filing. First action: identify behaviour band asserted by HMRC; check whether time limit applies (4-year normal / 6-year careless / 12-year offshore via TMA 1970 s.36A / 20-year deliberate). Second action: challenge discovery validity using Tooth v HMRC [2021] UKSC 17 + Hicks v HMRC [2020] UKUT 12 (TCC) — was the s.29 'discovery' valid + did the s.29(5) hypothetical-officer test (HMRC v Charlton [2012] UKUT 770) close the discovery route? Most discoveries fail on (b) where records were complete + agent disclosure adequate. Statutory review then FTT if needed. Scenario 4 — Information notice under FA 2008 Sch 36. Identify type: taxpayer notice (para 1) / third-party notice (para 2) / identity-unknown (para 5). Check reasonableness of request scope. Identify protected materials: legal professional privilege (para 18 absolute) + tax adviser privilege (para 24A narrow). Appeal route: para 29 to FTT for taxpayer notices. Most Sch 36 notices are valid + cooperation is the appropriate response; scope-pushing is the negotiation lever. Scenario 5 — COP9 letter received — emergency response protocol. Week 1: instruct specialist tax counsel via leading tax chambers; instruct forensic accountant; preserve all records; do not contact HMRC informally. Counsel + accountant scope Outline Disclosure within 60-day window. Specialist counsel ESSENTIAL — this is the canonical example. See cop9-and-cdf page worked example. Scenario 6 — Let Property Campaign self-serve disclosure for accidental landlord. GOV.UK online portal, Disclosure Reference Number, 90-day disclosure window, Sch 41 FA 2008 Failure to Notify framework with LPC reduced penalty band (10%-15% typical for unprompted careless). Self-serve, no 'LPC specialist' needed. See voluntary-disclosure-mechanisms worked example. Scenario 7 — Digital Disclosure Service for prior offshore non-compliance. Particularly relevant for offshore crypto positions before CARF data feed begins 1 January 2026. Sch 24 (if inaccuracy on submitted returns) or Sch 41 (if non-notification) regime applies with offshore enhancement bands. Sch 18 F(No.2)A 2017 Failure to Correct 200% penalty applies for years to 5 April 2017. Self-serve possible for straightforward positions; qualified accountant for complex multi-year + multi-jurisdiction; specialist counsel for substantial sums + fraud risk. Scenario 8 — Time To Pay arrangement when unable to pay assessed tax. Direct HMRC contact: 0300 200 3835 (Business Payment Support Service) or 0300 200 3822 (Self Assessment debt). No third-party intermediary required. HMRC officer assesses ability to pay, agrees instalment schedule, sets interest position. Self-serve. 'TTP specialist firm' £500+ markup is pure markup over a process designed for direct taxpayer-HMRC engagement. Scenario 9 — VAT inspection visit. Pre-visit: assemble VAT records for inspection period; review inspection notice for scope; consider Sch 36 information notice route if scope unreasonable. During visit: cooperate within scope; do not volunteer information outside scope; take notes; do not make statements about historical behaviour without consideration. Post-visit: HMRC will issue findings letter; respond in writing; statutory review + FTT route under VATA 1994 s.83 if dispute. Qualified accountant typically attends; self-serve for straightforward small-trader inspections. Scenario 10 — R&D claim post-enquiry. R&D enquiries since 2023 HMRC focus area; technical complexity warrants specialist engagement. NOT 'R&D defence specialist firm' £20,000+ markup; rather, specialist tax counsel via tax chambers (CIOT R&D Tax Committee members) at standard chambers rates + technical R&D consultant for substantive technical content. R&D claim defence is a genuine specialist area where firm-level markup is materially excessive. Scenario 11 — Statutory review request — when worth using. Useful filter for clear-cut decisions where HMRC may have applied wrong rule or missed evidence. Less useful for fact-specific reasonable-excuse or behaviour-band disputes where same HMRC department will likely reach same conclusion. 30-day window from HMRC decision under TMA 1970 s.49A; 45-day review conclusion target; 30-day FTT notification window then runs from review conclusion. Free to taxpayer. Scenario 12 — FTT late appeal — Martland framework. Missed 30-day appeal window. File Form T240 + separate Rule 20(4) application for permission. Apply Martland v HMRC [2018] UKUT 178 (TCC) framework: (1) seriousness/significance of delay; (2) reasons for delay; (3) all-circumstances evaluation including merits + prejudice + finality interest. Late-appeal applications NOT generous — file promptly when discovered. Self-serve for short delays with clear explanation; specialist counsel for material delays + substantive amounts. Eight anti-charlatan patterns follow with statutory rebuttals — see structured cards below.

    How it works

    Anti-charlatan pattern 1 — 'HMRC investigation specialist £8,000+ retainer'

    Marketing claim: cold-pitch firm offers 'HMRC investigation specialist' service on £8,000-15,000 retainer for any HMRC enquiry letter. Reality: most s.9A enquiries are routine compliance checks closed within 6-12 months with no penalty or modest adjustment. Initial response is acknowledgement + scoped record provision — accountant-led or self-serve. Specialist tax counsel via tax chambers (11 New Square / Pump Court Tax Chambers / Devereux Chambers / Old Square Tax Chambers / 15 Old Square) at standard chambers rates becomes appropriate for substantive disputes, technical complexity, or quantum justifying engagement — NOT for opening response. The 'investigation specialist' retainer markup is the issue; specialist engagement at appropriate level is fine.

    Anti-charlatan pattern 2 — 'Penalty appeal specialist no-win-no-fee 30% contingent'

    Marketing claim: cold-pitch firm offers penalty appeal on 30% contingent of any penalty saved. Reality: most reasonable-excuse penalty appeals are self-serve via Perrin v HMRC [2018] UKUT 156 (TCC) 4-stage framework. Sch 55 + Sch 56 reasonable excuse defence (para 23 / para 16) is well-documented + FTT outcomes predictable for genuine medical/bereavement/fire-flood/reliance-on-competent-adviser scenarios. Form T240 + statement of grounds = self-serve. For most fixed-penalty + small-quantum cases, the contingent fee model is built around volume; the firm's economics depend on % of taxpayers paying contingent on penalties they could have appealed for free.

    Anti-charlatan pattern 3 — 'COP9 specialist £15,000-40,000 retainer'

    Marketing claim: 'COP9 specialist firm' offers full COP9 service on £15,000-40,000 retainer. Reality: COP9 IS genuinely specialist work where qualified specialist tax counsel via leading tax chambers is essential. The issue is NOT engaging specialist help — it is the retainer markup over the actual cost structure. Properly assembled team: specialist tax counsel (silk or senior junior at standard chambers rates £300-£2,500/hour depending on seniority) + forensic accountant + solicitor coordination = typically £25k-£60k+ for mid-complexity COP9 fully assembled. Firm-level retainer often does NOT include independent specialist counsel — the genuinely warranted component. Engage counsel directly + ensure forensic accountant scope. See cop9-and-cdf page.

    Anti-charlatan pattern 4 — 'Tribunal advocate £5,000 per hearing'

    Marketing claim: 'tribunal advocate' offers per-hearing representation at £5,000+. Reality: FTT permits taxpayer self-representation at all levels (Basic / Standard / Complex / Default Paper) — no requirement for counsel or solicitor. Default Paper cases have no oral hearing at all. Basic-category cases are single oral hearing at regional venue, accessible to lay taxpayer. Where specialist counsel adds value: substantive law disputes at Standard or Complex level; quantum justifying engagement; technical area requiring specialist expertise. Standard chambers rates for tax counsel (not 'tribunal advocate' firm markup) apply — typically lower than firm-level pricing for equivalent expertise.

    Anti-charlatan pattern 5 — 'WDF disclosure specialist £10,000+'

    Marketing claim: 'Worldwide Disclosure Facility specialist' offers WDF service at £10,000+. Reality: WDF closed in 2018. Current general voluntary disclosure route is DDS via GOV.UK online process — self-serve. For offshore crypto holdings affected by CARF January 2026, the same DDS route applies (pre-CARF data feed). The 'WDF specialist' marketing is a multi-year-out-of-date legacy pitch; the underlying need (offshore disclosure) is real but the mechanism is different + self-serve.

    Anti-charlatan pattern 6 — 'Let Property Campaign specialist £3,000+'

    Marketing claim: 'LPC specialist firm' offers Let Property Campaign disclosure at £3,000-5,000 fixed fee. Reality: LPC is HMRC's published facility designed for self-serve via GOV.UK online process — notify, calculate, submit, settle. Reduced penalty band (10%-30% typical) is structured into the facility regardless of who handles it. Qualified accountant for complex multi-year + multi-property cases at standard rates; self-serve fully feasible for accidental landlord scenarios. The 'LPC specialist' markup is pure markup over a self-serve HMRC facility. See voluntary-disclosure-mechanisms worked example (Sarah / accidental landlord).

    Anti-charlatan pattern 7 — 'Time to Pay specialist £500+'

    Marketing claim: 'TTP specialist' offers Time To Pay arrangement negotiation at £500+ fixed fee. Reality: Time To Pay is direct taxpayer-HMRC engagement via published phone numbers (0300 200 3835 Business Payment Support; 0300 200 3822 Self Assessment debt). HMRC officer assesses ability to pay + agrees instalment schedule + sets interest position. No third-party intermediary required or expected by HMRC. The 'TTP specialist' fee is markup over a direct-contact process; the taxpayer's position is better presented directly than via intermediary.

    Anti-charlatan pattern 8 — 'R&D claim defence specialist £20,000+ post-enquiry'

    Marketing claim: 'R&D defence specialist firm' offers post-enquiry R&D claim defence at £20,000-40,000+ retainer. Reality: R&D claim enquiries since HMRC's 2023 enforcement focus genuinely DO benefit from specialist engagement for substantive technical disputes. The issue is: firm-level fees often exceed counsel rates available via CIOT R&D Tax Committee members + specialist chambers. Better-assembled team: specialist tax counsel via chambers (standard rates) + independent technical R&D consultant for substantive content + accountant for tax-technical work. Total often materially less than firm-level retainer. Plus R&D enquiry defence at FTT-Complex level can opt out of costs regime under Rule 10(1)(c)(ii) — accessible substantive dispute path.

    Who this applies to + key conditions

    Statute + manual references

    Primary: Aggregates statute from: enquiry-types-and-time-limits, penalty-regime, statutory-review-and-ftt-procedure, cop9-and-cdf, voluntary-disclosure-mechanisms.

    Related: TMA 1970 s.9A, s.29, s.31, s.34, s.36, s.36A (inserted by FA 2019 s.80 + Sch 11), s.49A-G, s.55, s.106A (inserted by FA 2000 s.144); Sch 24 FA 2007; Sch 55 + 56 FA 2009 (para 16 reasonable excuse for late payment); Sch 41 FA 2008; Sch 18 F(No.2)A 2017; FA 2008 Sch 36 (information notice powers); Tribunal Procedure (FTT) (Tax Chamber) Rules 2009 SI 2009/273; VATA 1994 s.83 (VAT appeal jurisdiction); Sch 26 FA 2021 (VAT points-based penalties from 1 January 2023)

    HMRC manual: EM1500/3200/8000 (enquiry); CH60000-CH80000 (penalties); ARTG2000-8000 (appeals/reviews); CH150000 (offshore matters); CH73000 (Sch 41)

    Case law: Tinkler v HMRC [2021] UKSC 39; Perrin v HMRC [2018] UKUT 156 (TCC); Pendragon plc v HMRC [2015] UKSC 37; Auxilium Project Management v HMRC [2016] UKFTT 249; Leach v HMRC [2019] UKFTT 352; Data Select Ltd v HMRC [2012] UKUT 187 (TCC) — superseded by Martland for late appeals; Martland v HMRC [2018] UKUT 178 (TCC) — current late-appeal lodestar applying Denton v TH White; Tooth v HMRC [2021] UKSC 17; Hicks v HMRC [2020] UKUT 12 (TCC); HMRC v Charlton [2012] UKUT 770 (TCC) — hypothetical officer test for discovery

    Common mistakes + traps

    Worked example

    Aggregate — this page is itself the scenarios collection; for individual worked examples see the specific sub-pages (penalty-regime, statutory-review-and-ftt-procedure, cop9-and-cdf, voluntary-disclosure-mechanisms)

    Cross-page worked examples are: Tom hospitalised + late-filing appeal (penalty-regime); Maya inaccuracy penalty + FTT Basic (statutory-review-and-ftt-procedure); Daniel COP9 + offshore consultancy income + Singapore account (cop9-and-cdf); Sarah accidental landlord + LPC self-serve (voluntary-disclosure-mechanisms); Priya sole-trader s.9A enquiry response (enquiry-types-and-time-limits).

    1. Each sub-page works through one canonical scenario from start to finish with cost analysis + specialist-counsel-warranted assessment.
    2. This scenarios + anti-charlatan page consolidates the editorial position across the cohort: self-serve where statute makes it accessible; appropriately-scoped professional engagement where complexity warrants; specialist counsel via leading tax chambers where the work is genuinely specialist (COP9 + substantive law + complex transfer pricing).
    3. The eight anti-charlatan patterns are summarised in the How It Works section above with statutory rebuttals.
    4. Across the cluster the consistent message is: predatory 'tribunal/HMRC specialist' market is real + identifies a genuine need (anxious taxpayers facing complex procedural systems) + then over-prices the response substantially. The editorial alternative is: understand the framework well enough to self-serve where possible + engage specialist counsel via chambers (not firm markup) where genuinely needed.
    5. Readers using this cluster for actual enquiry/penalty response should: identify which scenario / sub-page most closely matches their facts; read that page's worked example for response sequence; consider whether self-serve / accountant / specialist counsel level applies; engage at appropriate level via the editorial-signposted routes (CIOT chambers directory; Bar Council direct access; Tax Bar member chambers).
    6. For COP9: instruct specialist tax counsel via chambers within 7-10 days of letter receipt; do not delay; do not contact HMRC informally.
    7. For all other scenarios: most response sequences fit within self-serve or qualified-accountant frameworks at materially lower cost than firm-level 'specialist' marketing implies.

    Outcome: The cluster's editorial position: HMRC enquiry + tribunal territory is genuinely procedurally complex + appropriately uses qualified specialist help WHERE specialist help is genuinely warranted (COP9 + substantive law disputes + technical transfer pricing). It is NOT a uniformly-specialist area requiring £5k-40k retainers across the board — most routes are self-serve via established statutory + procedural frameworks. The 'tribunal/HMRC specialist' cold-pitch market is the issue, not specialist tax counsel via leading chambers at appropriate level.

    How this connects to the rest of the framework

    Enquiry types + time limits →

    Scenarios 2 (s.9A enquiry), 3 (discovery), 4 (Sch 36 notice) work through specific enquiry-type response sequences.

    Penalty regime + reasonable excuse →

    Scenarios 1 (first late-filing penalty) directly applies Perrin v HMRC framework + reasonable excuse defence under Sch 55 para 23.

    Statutory review + FTT procedure →

    Scenarios 11 (statutory review) + 12 (Martland late appeal) work through the FTT procedural pathway.

    COP9 + CDF →

    Scenario 5 (COP9 emergency response) is the canonical specialist-counsel-essential case.

    Voluntary disclosure mechanisms →

    Scenarios 6 (LPC), 7 (DDS offshore + crypto pre-CARF) work through voluntary disclosure pathways.

    /downloads/hmrc-late-filing-appeal →

    Self-serve template for Scenario 1 first-time late-filing penalty appeal.

    Frequently asked questions

    What happens if I miss the Self Assessment deadline?+
    The Self Assessment deadline is 31 January (online filing) for the previous tax year. Miss it and HMRC apply an automatic £100 penalty. Beyond that: £10 per day from 3 months late (capped at £900), 5% of tax due at 6 months late, and another 5% at 12 months late, under Schedule 55 of the Taxes Management Act 1970. If you have a genuine reason (serious illness, bereavement, technical issue with HMRC's systems) you can appeal with evidence; HMRC accepts reasonable excuse appeals in most genuine cases.
    Do I need an accountant or can I file Self Assessment myself?+
    Legally you can file Self Assessment yourself via gov.uk for free, most simple sole-trader returns (single income source, basic expenses) are realistic to self-file. An accountant adds real value when: your trading profit is above £40,000 (extraction-strategy decisions matter), you have multiple income streams (PAYE + self-employment + property + dividends), you've crossed the £90,000 VAT threshold, you're considering incorporation, or you have an HMRC enquiry. Expect to pay £400-£1,500/year for a typical sole-trader accountant; the cost is itself a deductible expense.
    How do payments on account work?+
    When your Self Assessment tax bill exceeds £1,000 for the first time, HMRC requires payments on account toward NEXT year's tax. Half the current bill is due 31 January (alongside the current bill); the other half is due 31 July. So your first January after crossing the threshold can hit with a double-bill: last year's balance + first payment on account. Adjust via Form SA303 if you expect next year's income to drop substantially. Payments on account don't apply if more than 80% of your tax is collected via PAYE.
    How do I find specialist tax counsel via chambers without going through a 'specialist firm'?+
    CIOT (Chartered Institute of Taxation) maintains a Tax Bar Member Chambers directory at tax.org.uk. Leading tax chambers: 11 New Square, Pump Court Tax Chambers, Devereux Chambers, Old Square Tax Chambers, 15 Old Square. Bar Council's Direct Access Portal (directaccessportal.co.uk) allows direct lay-client instruction of counsel for many matters. For COP9 a solicitor-instructed structure is generally preferable; for FTT advocacy in substantive disputes direct access can work. Initial 30-60 minute consultation is standard practice and often very low cost or fixed-fee.
    How do I know whether my case needs specialist counsel vs accountant vs self-serve?+
    Rough framework: (a) self-serve where statutory route is well-defined + quantum is modest + facts are clear (most penalty appeals, LPC, DDS routine, TTP, opening response to s.9A enquiry); (b) accountant where existing relationship covers it + technical content is in standard practice scope; (c) specialist counsel via chambers where COP9 / substantive law dispute / technical transfer pricing / quantum justifies engagement. See sub-page worked examples for specific patterns.
    What if HMRC's enquiry letter doesn't actually cite s.9A — is it still a formal enquiry?+
    A formal s.9A enquiry MUST cite s.9A in the notice (or s.12AC for partnerships, Sch 18 para 24 FA 1998 for companies). If the letter does not cite the statutory provision and just asks general questions, it is informal — you have no statutory duty to respond beyond reasonable courtesy. Write back asking HMRC to confirm whether this is a formal s.9A enquiry. The procedural framework matters.
    Can I challenge HMRC's behaviour-band assertion (careless vs deliberate)?+
    Yes — behaviour band drives both time limit AND penalty band, so it is the central battleground in many enquiries. The taxpayer evidences contemporaneous decision-making, reliance on competent adviser, HMRC guidance followed at the time, complexity of the matter. Auxilium Project Management v HMRC [2016] UKFTT 249 + Jonas v HMRC [2017] UKFTT 392 provide FTT analysis frameworks. The shift from 'careless' to 'innocent' (no penalty) or from 'deliberate' to 'careless' (lower band + shorter time limit) is often the most economically valuable move in a penalty/discovery dispute.

    Free + regulated-body resources

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