Schedule 24 FA 2007 Penalty Mitigation: Landlord Disclosure Quality, Suspension and Tooth-Era Bands

Schedule 24 of the Finance Act 2007 sets the inaccuracy-penalty bands that bite when HMRC opens an enquiry into a landlord's tax return and finds the figures wrong. The headline maxima (30 per cent careless, 70 per cent deliberate not concealed, 100 per cent deliberate and concealed, with offshore Category 2 and Category 3 uplifts taking the deliberate-and-concealed maximum to 200 per cent) sit on the front of every HMRC enquiry letter and are walked at length in our band-matrix companion page. This page is the mitigation-mechanics depth. Where the band matrix decides which maximum applies, the mitigation mechanics decide what the landlord actually pays.

Four operational levers move most landlord Schedule 24 cases from the maximum towards zero. The behaviour-band selection itself is the largest (a deliberate finding doubles or triples the maximum compared to careless; on a post-Tooth analysis many cases that HMRC opens as deliberate fall back to careless). The quality-of-disclosure reduction under paragraph 9 is the second. The suspension mechanic under paragraph 14 is the third, heavily under-used in landlord cases. The reasonable-excuse defence under paragraph 18 is the fourth. This page walks each layer in operational depth, surfaces the F-5 misconception on the careless-unprompted 0 per cent floor, and maps six worked landlord penalty calculations onto the framework.

The behaviour-band reset after HMRC v Tooth

Schedule 24 paragraph 3 sets three behaviour categories: careless (failure to take reasonable care), deliberate but not concealed (deliberate inaccuracy without active concealment), and deliberate and concealed (deliberate inaccuracy with active concealment such as false invoices, third-party bank account routing or document destruction). The band fixes the standard maximum penalty under paragraph 4. The band is therefore the largest single argument in any Schedule 24 penalty negotiation.

The Supreme Court decision in HMRC v Tooth [2021] UKSC 17 (judgment 14 May 2021) materially narrowed the deliberate-behaviour test. The court held that deliberate, for paragraph 3 purposes, requires the taxpayer or a person acting on their behalf to have known the statement to be false at the time it was made. Negligent, careless, reckless and wilful-blindness conduct do not cross the threshold. The pre-Tooth HMRC practice of characterising a wide range of conduct as deliberate (including cases where the taxpayer should have known) does not survive.

For landlords the operational consequence is that many enquiry letters that open with deliberate characterisation should be tested rigorously against the Tooth subjective-knowing-falsity standard. The downstream stakes are large: a 70 per cent or 100 per cent deliberate maximum carries with it a 0 per cent floor differential of 20 or 30 percentage points (per paragraph 10) rather than the careless 0 per cent unprompted / 15 per cent prompted floor at the 30 per cent maximum. A successful band-down argument from deliberate not concealed to careless can move a penalty exposure from, say, £14,000 to £1,800 on the same underlying tax loss before any quality-of-disclosure reduction. Our discovery time limits page walks how the same Tooth test also shrinks the 20-year window under s.36(1A) of TMA 1970.

The quality-of-disclosure reduction under paragraph 9

Once the band is fixed under paragraph 3 and paragraph 4 (Category 1) or paragraph 4A (offshore Categories 2 and 3), paragraph 9 sets out the disclosure mechanic that moves the penalty from the maximum towards the floor in paragraph 10. A person discloses an inaccuracy by:

• Telling HMRC about it. Clear admission of the scope, periods and amounts of the inaccuracy. Vague or hedged admissions score low; clear written statement of what went wrong and across which years scores high.
• Giving HMRC reasonable help in quantifying it. Calculations, schedules, supporting documents that allow HMRC to verify the under-assessment. Self-prepared rental-income schedules, capital-vs-revenue analysis, year-by-year tax-loss computations.
• Allowing HMRC access to records to check the figures. Rental schedules, bank statements, property contracts, lettings-agent statements, mortgage statements.

All three limbs feed into the reduction from the paragraph 4 maximum towards the paragraph 10 floor. Full marks on all three drops the penalty to the floor; zero marks leaves it at the maximum; partial marks land somewhere between. HMRC weights the three limbs qualitatively rather than mechanically. In operational practice the helping limb (full quantification of the under-assessment, enabling HMRC to close efficiently) typically carries the largest practical weight because it most directly advances HMRC's case-closure objective. The telling limb is necessary but, on its own, near-worthless if not accompanied by quantification. The giving limb is usually a tick-box compliance issue rather than a discretion swing factor.

The commonly cited 30 per cent / 40 per cent / 30 per cent allocation between telling, helping and giving that appears in some practitioner writing is industry shorthand. It is not in the verbatim text of paragraph 9 and is not in current HMRC published guidance at CH82420 (unprompted and prompted disclosure) or CH82460 (giving access). Frame the operational weighting qualitatively where the case stakes turn on the precise reduction percentage; use the precise numbers only as a sense-check.

The paragraph 10 floors and the F-5 trap

Paragraph 10 sets the statutory floors below which paragraph 9 disclosure cannot reduce the penalty. The table is:

• 30 per cent standard (careless): 15 per cent prompted minimum / 0 per cent unprompted minimum.
• 70 per cent standard (deliberate not concealed): 35 per cent prompted / 20 per cent unprompted.
• 100 per cent standard (deliberate and concealed): 50 per cent prompted / 30 per cent unprompted.

The careless-unprompted 0 per cent floor is the single most-impactful operational lever in landlord cases where behaviour analysis lands in the careless band. With full telling, helping and giving on an unprompted disclosure, the penalty for a careless landlord-tax inaccuracy can be zero. Multi-year tax losses with full unprompted disclosure can therefore land entirely on the tax and statutory interest, with no penalty at all.

Suspension under paragraph 14: under-used and operationally valuable

Paragraph 14 allows HMRC to suspend all or part of a careless inaccuracy penalty by notice in writing. The suspension period cannot exceed two years (paragraph 14(2)(b)). Suspension is available only for careless penalties and only where a suspension condition would help the landlord avoid further careless inaccuracies (paragraph 14(3)). HMRC sets conditions specifying actions to be taken and a period in which to take them (paragraph 14(4)). On expiry, if the landlord satisfies HMRC that conditions were complied with, the suspended penalty or part is cancelled (paragraph 14(5)(a)). Otherwise it becomes payable (paragraph 14(5)(b)). A further careless paragraph 1 penalty during the suspension window makes the suspended penalty immediately payable (paragraph 14(6)).

Suspension is operationally valuable because, where conditions are met, the penalty is cancelled in full rather than merely reduced. The careless 30 per cent maximum becomes zero rather than a percentage between 0 per cent and 30 per cent. The lever therefore competes directly with the paragraph 9 quality-of-disclosure reduction on careless cases: a maximum-quality unprompted careless disclosure reaches the 0 per cent floor through paragraph 9; suspension reaches the same outcome (penalty cancelled) through a different route, while leaving the formal penalty assessment in place for as long as the suspension runs.

Typical suspension conditions in landlord cases include: file all self-assessment returns on time during the suspension period; engage a competent tax adviser for at least the next two tax years; maintain digital records compliant with Making Tax Digital for ITSA where in scope; complete an HMRC online learning module on the rental-income rules that gave rise to the original carelessness; supply HMRC with quarterly bookkeeping evidence on request. The defining feature is causation: the condition must connect to the original carelessness in a way that makes recurrence less likely.

HMRC has discretion to refuse suspension under paragraph 14(3) where, on the facts, no condition would meaningfully reduce the risk of further careless inaccuracies. Refusals can be appealed to the First-tier Tribunal alongside the underlying penalty assessment. Operationally, where HMRC refuses suspension at the assessment stage, the appeal arguments run on (a) whether a suitable condition could in fact be specified (the landlord proposes specific conditions), and (b) whether HMRC's stated grounds for refusal are reasonable on the facts. HMRC's published guidance at CH83110 sets out the operational position on suspension; the CC/FS10 taxpayer-facing factsheet covers the same ground in plain language.

Reasonable-excuse defence under paragraph 18

Paragraph 18 provides a statutory defence where the landlord had a reasonable excuse for the inaccuracy. The defence is independent of suspension and reduction; it operates as a complete bar to penalty rather than a reduction towards floor. The controlling Upper Tribunal authority is Perrin v HMRC [2018] UKUT 156 (TCC), which sets a four-stage test:

1. Was there an excuse?
2. Was the excuse objectively reasonable in the circumstances?
3. Did the excuse cause the failure?
4. Was the failure remedied without unreasonable delay once the excuse ended?

Common landlord scenarios that pass the Perrin test: serious illness during the return period (depression, oncology treatment, surgery with extended recovery); bereavement of a close family member during the filing window; HMRC system outage preventing electronic submission; theft or destruction of records following a domestic incident. Common scenarios that fail at stage 2 (objective reasonableness): "I didn't know I had to declare rental income" (rental-income declaration is a matter of basic compliance for which the landlord is expected to take advice); "my accountant didn't tell me" (depends on the supervisory relationship, covered next).

Agent error attribution operates differently under the Hanson v HMRC [2012] UKFTT 314 (TC) and David Collis v HMRC [2011] UKFTT 588 (TC) line of authority. Where the landlord gave the agent full and accurate disclosure of the facts and the agent's error was the agent's own (rather than driven by missing information from the landlord), the analysis supports a defence that the landlord took reasonable care in instructing the agent. The defence operates at two levels: (a) the band itself may be careful rather than careless on the original return, blocking Schedule 24 entirely; (b) failing that, a paragraph 18 reasonable excuse may still apply on the Perrin framework. The defensive discipline is documenting the disclosure trail to the agent and the supervisory relationship at the time the original return was filed. Our Perrin and Martland reasonable-excuse page covers the case-law in more depth.

Appeal route under TMA 1970 s.31A

Section 31A gives a 30-day window from the date of the penalty notice to lodge a notice of appeal. The window applies equally to the substantive penalty assessment and to a refusal to suspend under paragraph 14. Appeals go to the First-tier Tribunal (Tax Chamber) under the Tribunal Procedure (First-tier Tribunal) (Tax Chamber) Rules 2009 (SI 2009/273). Late appeals require a reasonable-excuse application under the three-stage framework in Martland v HMRC [2018] UKUT 178 (TCC): (i) the length of the delay, (ii) the reasons for the delay, (iii) all the circumstances of the case.

HMRC's Alternative Dispute Resolution process is available alongside the FTT route. ADR involves a trained HMRC mediator (and can include an independent external mediator) facilitating discussions between the case officer and the taxpayer's representative. Engagement with ADR does NOT pause the 30-day appeal clock; the appeal must be lodged within the window even where ADR is in train. ADR is operationally most useful where the dispute is about evidence weighting (whether records support the band the taxpayer claims) rather than statutory interpretation.

Six worked Schedule 24 mitigation calculations for landlords

Scenario 1: Careless unprompted, full quality, on-shore UK rental. A landlord with two years of careless under-declaration of £15,000 each year (failure to keep adequate receipts; capital improvements miscoded as repairs). Total tax loss £6,000 per year x 2 = £12,000 across both years. Behaviour: careless. Unprompted disclosure via the Let Property Campaign route before any HMRC contact. Full telling, helping and giving. Paragraph 10 careless-unprompted floor: 0 per cent. Effective penalty: £0. Landlord pays £12,000 tax plus statutory interest only. F-5 reminder: the floor applies even if the inaccuracy is older than 12 months because Schedule 24 carries no 12-month qualifier (see callout above).

Scenario 2: Careless unprompted, partial quality (telling only), 4 years late. Same £12,000 tax loss across two years but disclosure four years after the original returns and only telling without quantification or document access. Unprompted (no HMRC contact). The 12-month cliff some advisers cite does NOT apply here; that is the Schedule 41 case A vs case B framework, not Schedule 24. The 0 per cent careless-unprompted floor remains available. What moves is the quality-of-disclosure reduction: with telling alone (and HMRC operationally weighting helping highest), the achieved reduction is materially less than the full 30-percentage-point window from 30 per cent maximum to 0 per cent floor. A working estimate is a reduction of roughly half the available window, giving an effective penalty around 15 per cent. On £12,000 tax loss this is around £1,800. The lesson: the floor is preserved by behaviour-and-prompt-status; the actual percentage paid is driven by quality. Operational discipline: provide full helping and giving to land at the floor.

Scenario 3: Careless prompted (HMRC nudge letter triggered disclosure), full quality. Same £12,000 tax loss as scenario 1. HMRC sent a nudge letter referencing Land Registry data; landlord then engaged adviser and disclosed. Prompted (HMRC contact came first). Careless-prompted floor: 15 per cent. With full quality, achieved reduction lands at the floor: 15 per cent. Effective penalty: 15 per cent x £12,000 = £1,800. Compared to scenario 1's £0, the unprompted vs prompted lever is worth £1,800 on this fact pattern. The operational implication: self-disclose before the nudge letter arrives where possible.

Scenario 4: Deliberate not concealed, unprompted, full quality. Landlord knowingly omitted £25,000 of cash rental per year over two years from filed returns. Tax loss £20,000. Behaviour: deliberate not concealed on a Tooth analysis (knew the statement to be false at time of filing; no active concealment beyond simple omission). Unprompted disclosure. Paragraph 10 floor: 20 per cent. Effective penalty: 20 per cent x £20,000 = £4,000. Cross-link: deliberate behaviour also unlocks the 20-year discovery window under TMA 1970 s.36(1A), so HMRC's reach extends to multi-year exposures beyond the careless 6-year reach. If criminal-prosecution exposure exists, switch route to the Contractual Disclosure Facility under Code of Practice 9; LPC is the wrong route for deliberate cases where HMRC may pursue criminal proceedings.

Scenario 5: Deliberate and concealed, prompted, full quality. Landlord ran £40,000 per year cash rental through a relative's bank account for five years and never declared it. Tax loss £80,000. Behaviour: deliberate and concealed (third-party bank account routing is a textbook concealment indicator). HMRC-prompted (discovered via informant). Paragraph 10 floor: 50 per cent. With full quality, effective penalty: 50 per cent x £80,000 = £40,000. The s.36(1A) 20-year discovery window opens. CoP9 / CDF route should be considered for criminal-immunity protection; specialist representation territory.

Scenario 6: Category 2 offshore careless unprompted, full quality. Landlord with rental property in a Category 2 territory (partial information exchange); careless under-declaration; £30,000 tax loss over four years. Paragraph 4A offshore uplift takes the standard maximum from 30 per cent to 45 per cent. The unprompted floor under paragraph 10 uplifts in parallel: 0 per cent x 1.5 = 0 per cent in this case. Effective penalty with full quality: £0 (the floor remains at zero because zero multiplied by any factor is zero). The uplift bites where the achieved reduction is less than the full window; partial quality on a Category 2 careless unprompted disclosure can take the effective penalty up towards 45 per cent rather than 30 per cent. Spain, France, Portugal and most EU territories are Category 1 (full information exchange); the Category 2 / 3 uplifts apply mainly to certain non-EU jurisdictions and need verification against the current Treasury Order at paragraph 21A. Schedule 21 FA 2015 adds a separate asset-move penalty on top of the Schedule 24 offshore uplift where assets are moved from a specified territory to defeat HMRC; the two mechanisms stack rather than substitute.

The Sch 21 FA 2015 asset-move stacking layer

Where assets are moved from a specified (Category 2 or 3) territory to a non-specified territory with the main purpose of preventing or delaying HMRC's discovery, Schedule 21 FA 2015 imposes a separate asset-move penalty in addition to the Schedule 24 inaccuracy penalty. The asset-move penalty is calculated as 50 per cent of the underlying Schedule 24 penalty, and stacks on top rather than replacing it. Effective from 26 March 2015.

For a Category 3 deliberate-and-concealed inaccuracy with assets moved to defeat HMRC, the combined exposure is the Schedule 24 200 per cent maximum (Category 3 deliberate-and-concealed) plus the Sch 21 asset-move 50 per cent of that figure. On a £100,000 tax loss with no quality reduction, this is £200,000 (Sch 24) + £100,000 (Sch 21) = £300,000 combined. The Sch 21 penalty is not within Schedule 24 paragraph 14 suspension and does not enjoy the paragraph 10 mitigation floors. It is a separate statutory penalty with its own mitigation architecture.

Schedule 24 vs Schedule 41 vs Schedule 55 / 56: separation discipline

Schedule 24 is one of four separate penalty regimes that can apply on landlord tax-compliance failures. The regimes do different work and must not be conflated.

• Schedule 24 FA 2007 (this page): inaccuracy in a return already filed.
• Schedule 41 FA 2008: failure to notify chargeability at all (TMA 1970 s.7 obligation). The Schedule 41 case A vs case B framework at paragraph 13 carries the 12-month qualifier that is sometimes wrongly imported into Schedule 24. Our Schedule 41 failure-to-notify coverage walks the case A and case B mechanics.
• Schedule 55 FA 2009: late filing of returns. Procedural rather than substantive; separate fixed and tax-geared components.
• Schedule 56 FA 2009: late payment of tax assessed. Procedural; surcharges at 30 days, 6 months and 12 months past the due date.

On the same facts a landlord can face penalties under more than one regime. A landlord who never registered for self-assessment for some years (Schedule 41 territory), then filed inaccurate returns for later years (Schedule 24 territory), then filed late for further years (Schedule 55 territory), then paid late on the resulting assessments (Schedule 56 territory) is within all four regimes simultaneously on different limbs. Our HMRC late-landlord-tax-returns coverage separates Schedule 55 and Schedule 56 from the Schedule 24 inaccuracy mechanics covered here. Penalties do not double-count on the same tax loss but each regime applies to its own statutory failure.

Operational playbook for a Schedule 24 penalty assessment

The defensive framework on receipt of a Schedule 24 penalty notice runs:

1. Day 1 to 7. Identify the band HMRC has applied (careless / deliberate not concealed / deliberate and concealed) and the standard percentage. Identify whether the assessment is unprompted or prompted on HMRC's analysis. Identify which floor HMRC has applied under paragraph 10.
2. Day 7 to 14. Run the band-down analysis. On a deliberate-band assessment, apply the Tooth subjective-knowing-falsity test rigorously. If the underlying conduct is properly careless rather than deliberate, this is the single largest argument available.
3. Day 14 to 21. Run the quality-of-disclosure analysis. Is the achieved paragraph 9 reduction the full window from maximum to floor? If not, identify which limb (telling / helping / giving) is incomplete and remediate.
4. Day 21 to 28. On careless-band assessments, propose suspension conditions under paragraph 14. The proposal needs to specify causally-linked actions that would reduce the risk of further careless inaccuracies.
5. Day 28 to 30. Lodge a notice of appeal under s.31A within the 30-day window even if engaged in ongoing discussions with HMRC. ADR engagement does not pause the clock.
6. Where reasonable excuse applies. Frame the paragraph 18 defence on the four-stage Perrin test. This sits independently of the band, the quality reduction and suspension.

The four levers (band-down, paragraph 9 quality, paragraph 14 suspension, paragraph 18 reasonable excuse) are independent and operate cumulatively. The combined defensive position frequently reduces a maximum-maximum Schedule 24 exposure to zero or near-zero on careless landlord cases with full unprompted disclosure or successful suspension.

If you have received a Schedule 24 penalty assessment, are being told that the 0 per cent floor is gated by a 12-month qualifier, or are considering whether suspension might apply, the form at the foot of the page is the route to a structured first-pass assessment.