Let Property Campaign Penalty Calculator: Estimating Your Schedule 41 Exposure Before You Notify

A landlord at the decision moment between (i) notify LPC now, (ii) wait, or (iii) ignore needs a number to weigh the choice. The number is not produced by HMRC's internal penalty system (which is not public-facing) nor by an HMRC published online calculator (the gov.uk LPC pages walk the process, not the arithmetic). It is produced by walking the Schedule 41 paragraph 13 mitigation matrix manually against five inputs. This page is the structured walk-through. It shows the matrix in full, runs five fact-pattern examples, and identifies the four triggers where the calculator routes the landlord to specialist counsel rather than self-service LPC.

The matrix is not complex once visualised. Three behaviour bands by two prompted-or-unprompted statuses by three territory categories produce an 18-cell grid. Pick one cell per disclosure year (the same year can span multiple cells if behaviour shifted), multiply the floor by the year's undisclosed tax, sum across years, layer in interest, and present the total to HMRC at notification. The HMRC final penalty sits within a floor-to-maximum bracket; the floor is the start position for a complete-and-prompt disclosure.

The five calculator inputs

Every LPC penalty estimate uses the same five inputs. Get these right and the matrix produces a numerical estimate consistent with what HMRC's disclosure-response letter will return on the same facts.

Input 1: tax-years undisclosed

List every tax year where rental income should have been declared but was not. For most accidental landlords this is a contiguous block (4 to 8 years is typical). For some landlords there is a partial block (rental declared for some years, omitted for others). The calculator runs year-by-year; per-year inputs differ in tax due, in interest accrual (older years have accrued more), and sometimes in behaviour band (a landlord who was non-deliberate in early years can become deliberate after a clear warning, for example after an HMRC nudge letter on a different matter).

Input 2: gross rent and deductions per year

Per year, gross rents received less allowable deductions equals net property profit. Allowable deductions follow the standard property-income framework: agent fees, repairs (capital-vs-revenue boundary applies), insurance, ground rent and service charges, accountancy fees on the rental accounts, mortgage interest under the Section 24 finance-cost-restriction framework (interest is a 20% tax-reducer rather than a deduction from rental income for non-corporate landlords from 2020/21 onwards). The £1,000 property allowance under ITTOIA 2005 section 783A may apply for years where rents were below the threshold; from 2026/27 onwards the property allowance increases under separate legislation.

Input 3: behaviour self-assessment

Three categories under Schedule 41 paragraph 5. The categorisation is fact-sensitive and HMRC's call in the response letter may differ from the landlord's self-assessment.

• Non-deliberate. Honest mistake or careless error. The accidental landlord who never registered for self-assessment because they assumed PAYE or the letting agent covered it. The busy worker who let an obligation slip. The non-resident who thought NRL withholding was a final tax.
• Deliberate but not concealed. A knowing choice not to declare, with no further concealment steps. The landlord who knew the rental was taxable, decided not to file, and took no active concealment action.
• Deliberate and concealed. A knowing choice not to declare, with active concealment. Routing rental receipts through accounts in family-member names; false invoices to mask income; document destruction; deliberate omission from accountant-prepared accounts.

The legal threshold for deliberate is set by HMRC v Tooth [2021] UKSC 17: a conscious choice to omit or understate, knowing the income should have been disclosed. The honest-mistake population sits in non-deliberate. The conscious-omission population sits in deliberate not concealed. The active-concealment population sits in deliberate and concealed.

Input 4: prompted or unprompted status

Unprompted disclosure occurs where the landlord initiates the notification before HMRC has indicated awareness of the failure. Bright-line tests:

• No nudge letter received on the matter.
• No formal enquiry opened under TMA 1970 section 9A.
• No discovery assessment issued under TMA 1970 section 29.
• No Connect-system match formally notified.

HMRC v Hicks [2020] UKUT 12 (TCC) is the Upper Tribunal authority on the Schedule 41 prompted-vs-unprompted distinction in operation. The case clarifies that nudge letters fall on the informal-contact side of the line: a disclosure made within the nudge-letter response window before any formal enquiry can typically still be treated as unprompted in HMRC operational practice. Once HMRC has issued a section 9A enquiry or a section 29 assessment, the unprompted window closes.

Input 5: territory category

Schedule 41 paragraph 6A imports the offshore Category structure from the HMRC-published list at the offshore-evaders-penalties-territories page on gov.uk. The categorisation reflects information-exchange depth:

• Category 1 (1.0x multiplier). The UK plus offshore territories with full information exchange. Most EU member states post-DAC2 and post-CRS. The Channel Islands, Isle of Man post-CRS. Treaty-partner jurisdictions with full Tax Information Exchange Agreements and automatic exchange.
• Category 2 (1.5x multiplier). Offshore territories with partial information exchange. Bilateral TIEA partners without full automatic exchange. Certain Caribbean and Middle East jurisdictions historically (the list updates with treaty changes).
• Category 3 (2.0x multiplier). Offshore territories with no information exchange. A small and shrinking residual category as global treaty coverage expands. The list updates as treaties are signed; sessions verify currency at write time.

UK rental property is always Cat 1. The Category structure bites only on offshore rental. A UK-resident landlord with a UK rental property does not engage the Cat 2 or Cat 3 uplift on residence-alone grounds; the uplift is determined by where the income or asset is, not where the landlord is.

The Schedule 41 paragraph 13 mitigation matrix

The matrix below sets the operational floors and maxima. Pick the cell that matches the behaviour, status, and territory for the year being computed.

Unprompted disclosure floors

These are the LPC route's headline advantage. Available only while HMRC has not indicated awareness.

• Non-deliberate, within 12 months of when liability arose: 0% (Cat 1, 2, and 3 all start at 0% on the floor; the Category multipliers apply only above the floor).
• Non-deliberate, more than 12 months late: 10% Cat 1, 15% Cat 2, 20% Cat 3.
• Deliberate but not concealed: 20% Cat 1, 30% Cat 2, 40% Cat 3.
• Deliberate and concealed: 30% Cat 1, 45% Cat 2, 60% Cat 3.

Prompted disclosure floors

Engaged once HMRC has opened a formal enquiry or issued a discovery assessment.

• Non-deliberate: 10% Cat 1, 15% Cat 2, 20% Cat 3.
• Deliberate but not concealed: 35% Cat 1, 52.5% Cat 2, 70% Cat 3.
• Deliberate and concealed: 50% Cat 1, 75% Cat 2, 100% Cat 3.

Maxima (the top of the bracket)

• Non-deliberate: 30% Cat 1, 45% Cat 2, 60% Cat 3.
• Deliberate but not concealed: 70% Cat 1, 105% Cat 2, 140% Cat 3.
• Deliberate and concealed: 100% Cat 1, 150% Cat 2, 200% Cat 3.

The floor and the maximum form a bracket within which HMRC fixes the actual penalty using the quality-of-disclosure framework at CH82400 onwards. The framework weighs the telling (how much the landlord told HMRC about the failure), the helping (how the landlord assisted HMRC's enquiries), and the giving access (the documentary and information access provided). A complete-and-prompt disclosure sits at or near the floor; an incomplete or evasive disclosure pushes toward the maximum.

The computation per year

For each tax year being disclosed, the calculator runs three lines.

Line 1: tax due

Net property profit (gross rent less allowable deductions) at the landlord's marginal income tax rate for the year. For a basic-rate taxpayer (income within the basic-rate band including the rental), the rate is 20%. For a higher-rate taxpayer the rate is 40%. For an additional-rate taxpayer the rate is 45%. The Section 24 mortgage-interest restriction reduces tax by 20% of finance costs, not from rental income. The tax due is what should have been paid on the rental for that year.

Line 2: interest under TMA 1970 section 86

HMRC late-payment interest at Bank of England base rate plus 4 percentage points, accruing from the due date of each year's balancing payment (typically 31 January following the tax year) to the date of payment under the LPC settlement. Interest is not mitigated by the LPC route. For older years (2018/19, 2019/20, 2020/21), the interest layer can be substantial: at an effective rate around 7.5% averaged across the period, 5 years of accrued interest on £2,000 per-year underpaid tax sits around £2,800 to £3,200 cumulative.

Line 3: penalty under Schedule 41 paragraph 13

Floor (or higher within the bracket) applied to the year's tax due. For a non-deliberate, unprompted, UK-property year disclosed after 12 months, the floor is 10%. On £2,000 of underpaid tax, the floor-level penalty is £200. The maximum is 30%, giving £600. A complete-and-prompt disclosure typically settles at or near the floor.

The three lines sum to the disclosure total for the year. Sum across all undisclosed years to get the headline disclosure number to present at LPC notification.

Worked example 1: the 0% headline within 12 months

Hollingsworth-Estate inherited a property in late 2024 and let it from January 2025. The landlord never registered for self-assessment for 2024/25 because the income-tax obligation on rental income was not on Hollingsworth-Estate's radar. In March 2026 a friend mentioned that rental income requires a return; Hollingsworth-Estate realises the failure within 12 months of the 2024/25 tax becoming payable (31 January 2026).

Inputs

• Years undisclosed: 2024/25 only.
• Gross rent: £14,000 (3 months in 2024/25).
• Deductions: £4,200 (agent fees, insurance, minor repairs).
• Net profit: £9,800.
• Behaviour: non-deliberate (genuine oversight; no awareness of SA obligation).
• Status: unprompted (no nudge letter, no enquiry).
• Territory: Cat 1 UK.
• Realisation date: March 2026. The 12-month window from 31 January 2026 runs to 31 January 2027.

Computation

• Tax due: £9,800 × 20% basic rate = £1,960 (assuming basic-rate taxpayer overall).
• Interest: TMA 1970 section 86 from 31 January 2026 to disclosure date; at around 7.5% effective rate, around £40 to £60 for a disclosure within a few months of the due date.
• Penalty: 0% on the 2024/25 year (Schedule 41 paragraph 13 non-deliberate-unprompted-within-12-months floor).
• Disclosure total: around £2,000 to £2,020 (tax plus minimal interest plus zero penalty).

The headline benefit

The 0% floor is the rescue. Hollingsworth-Estate's disclosure window for the 0% floor closes on or around 31 January 2027 (12 months after the 2024/25 tax became payable on 31 January 2026). Disclosing after the window pushes the floor to 10%, costing an additional £196 (10% of £1,960). The 12-month qualifier is the structural feature of Schedule 41 paragraph 13 that rewards early notification by an accidental landlord.

Worked example 2: the 10% floor after 12 months

Rashleigh-Estate has 6 years of undisclosed rental on a single BTL property let since 2019. The landlord realises the failure in 2026 (a routine review of finances by a new financial adviser surfaced the unreported rents). The most recent year (2024/25) is on the borderline of the 12-month window; the earlier 5 years (2019/20 to 2023/24) are well past.

Inputs

• Years undisclosed: 2019/20, 2020/21, 2021/22, 2022/23, 2023/24, 2024/25.
• Gross rent: £18,000 per year × 6 = £108,000 cumulative.
• Deductions: 30% per year = £32,400 cumulative.
• Net profit: £75,600 cumulative.
• Behaviour: non-deliberate (sloppy assumption that the letting agent's processing of rents covered the tax position).
• Status: unprompted (no nudge letter).
• Territory: Cat 1 UK.

Computation

• Tax due: £75,600 × 20% basic rate (assuming basic-rate-only profile) = £15,120 cumulative across the 6 years (around £2,520 per year).
• Interest: TMA 1970 section 86 from each year's due date. Cumulative interest from 31 January 2021 (for 2019/20) onwards is around £3,500 to £4,000 depending on the rate trajectory.
• Penalty: 10% on all 6 years (Schedule 41 paragraph 13 non-deliberate-unprompted-after-12-months floor for Cat 1). The most recent year 2024/25 may qualify for the 0% floor if the disclosure date is before 31 January 2027; otherwise 10%. Assuming the after-12-months floor on all 6 years: £15,120 × 10% = £1,512.
• Maximum within the bracket: 30% Cat 1 = £4,536.
• Disclosure total at floor: £15,120 plus around £3,750 plus £1,512 = around £20,400.

The bracket presentation

The calculator should display both the floor (£1,512 penalty) and the maximum (£4,536). The landlord is negotiating within the bracket using the quality-of-disclosure framework. A complete documentary pack (bank statements, agent statements, expense records, mortgage interest certificates for the Section 24 calculation) with prompt response to HMRC's correspondence pushes the position toward the floor.

Worked example 3: the 35% prompted floor after a nudge letter

Belmount-Estate holds 4 BTL properties. HMRC sent a nudge letter on 12 February 2026 indicating awareness of likely undisclosed rental income (the letter references Land Registry data and bank-feed pattern recognition). Belmount-Estate has 5 years of undisclosed rental. The landlord knew the rental was taxable; the omission was a knowing choice rather than an oversight, but no active concealment was undertaken.

Inputs

• Years undisclosed: 2020/21, 2021/22, 2022/23, 2023/24, 2024/25.
• Gross rent: £85,000 per year × 5 = £425,000 cumulative.
• Deductions: 25% per year = £106,250 cumulative.
• Net profit: £318,750 cumulative.
• Behaviour: deliberate but not concealed.
• Status: PROMPTED (nudge letter received 12 February 2026).
• Territory: Cat 1 UK.

Computation

• Tax due: £318,750 at a marginal-rate mix. Assuming higher-rate (40%) on the majority of the rental (the landlord's other income absorbed the basic-rate band), tax due is around £127,000 cumulative.
• Interest: TMA 1970 section 86 from each year's due date. Cumulative interest on £127,000 spread over 5 years is around £30,000 to £35,000.
• Penalty: 35% on all 5 years (Schedule 41 paragraph 13 deliberate-not-concealed PROMPTED floor for Cat 1). £127,000 × 35% = £44,450.
• Maximum within the bracket: 70% Cat 1 = £88,900.
• Disclosure total at floor: £127,000 plus £32,500 plus £44,450 = around £204,000.

The counterfactual: what if Belmount-Estate had notified before the nudge letter

The unprompted floor at deliberate-not-concealed is 20%. Had Belmount-Estate notified on 11 February 2026 (one day before the nudge letter), the floor would have been 20% rather than 35%. £127,000 × 20% = £25,400. The differential between the 20% unprompted floor and the 35% prompted floor on the same £127,000 tax is £19,050. The cost of having waited until HMRC indicated awareness, on these facts, is just under £20,000 on the penalty alone, before considering the harder position the landlord faces on quality-of-disclosure framing within the higher bracket.

The structural lesson

The rising-cost-of-delay dynamic is steep at the deliberate-not-concealed band. Each percentage point of higher floor on a six-figure tax exposure equates to thousands of pounds. Sessions writing on the LPC route should illustrate this delta clearly to teach the deadline-driven decision logic.

Worked example 4: offshore Cat 2 case that routes to specialist counsel

Vandenberg-Estate is UK-tax-resident and owns a residential rental property in a Cat 2 partial-information-exchange jurisdiction. 8 years of undisclosed rental are in scope. Local-currency rent equivalent is £35,000 per year; expenses 20% per year. Pre-30-September-2018 years (2014/15 to 2017/18) engage the Failure-to-Correct overlay under FA 2017 Schedule 18.

Inputs

• Years undisclosed: 2014/15 to 2021/22 (8 years).
• Gross rent: £35,000 per year × 8 = £280,000 cumulative.
• Deductions: 20% per year = £56,000 cumulative.
• Net profit: £224,000 cumulative.
• Behaviour: deliberate but not concealed (knowing omission; no active concealment).
• Status: unprompted (no nudge letter).
• Territory: Cat 2.
• Pre-30-September-2018 years: 2014/15, 2015/16, 2016/17, 2017/18 (4 years engage the FtC overlay).

The calculator routes to specialist counsel

This is the case where self-service LPC is not the right route. Four reasons:

• The rental property is offshore. LPC accommodates UK-residential-rental only. Offshore rental routes through the Worldwide Disclosure Facility under the DDS umbrella.
• Pre-30-September-2018 years engage the Failure-to-Correct overlay under FA 2017 Schedule 18. The minimum penalty under FtC is 200% of unpaid UK tax, reducible to 100% on a complete unprompted disclosure. The FtC layer sits on top of (not in place of) the Schedule 41 mitigation matrix. This is materially heavier than the Cat 1 UK landlord profile.
• The Cat 2 multiplier (1.5x) elevates both the floor (20% becomes 30%) and the maximum (70% becomes 105%) under Schedule 41 paragraph 13.
• The asset-based penalty regime under FA 2016 Schedule 22 may engage where lost tax exceeds £25,000 in any year (asset-based penalty up to 10% of property value).

The routing-to-specialist trigger

The calculator surfaces a hard stop on these facts. The output is not a number; it is a routing message: speak to a tax-investigation specialist before notifying anything. The reasons: (1) the WDF route inside DDS, not LPC; (2) the FtC overlay computation, which the standard LPC calculator does not include; (3) the asset-based penalty regime, which the standard LPC calculator does not include; (4) the potential CoP9 / CDF criminal-prosecution-protection question, which a non-specialist disclosure can crystallise rather than defer. Each of these layers requires specialist tax-investigation input before the notification step.

Worked example 5: the early-notify advantage for a borderline year

Padworth-Estate has 3 years of undisclosed rental on a single residential BTL property: 2022/23, 2023/24, and 2024/25. The most recent year (2024/25) is within the 12-month window for the 0% floor (deadline 31 January 2027). The earlier 2 years (2022/23 and 2023/24) are past the 12-month window and attract the 10% floor. Behaviour is non-deliberate. Status is unprompted (no nudge letter).

The early-notify-advantage computation

Net profit per year is £8,000. Tax due per year at basic rate (20%) is £1,600. The disclosure runs:

• Disclosing NOW (before 31 January 2027): 0% floor on 2024/25 (£0 penalty) plus 10% floor on 2022/23 and 2023/24 (£320 penalty). Total penalty: £320.
• Disclosing AFTER 31 January 2027: 10% floor on all 3 years. Total penalty: £480.
• Early-notify advantage: £160 saved by disclosing before the 12-month deadline (the 10% differential on the 2024/25 year's £1,600 tax).

The actionable line

For Padworth-Estate, the calculator's most operationally useful output is not the total penalty (which is small in absolute terms on this fact pattern). It is the early-notify-advantage line: a £160 saving by notifying before 31 January 2027. The line gives Padworth-Estate a deadline-driven nudge to act now rather than defer. For larger borderline cases (a landlord with higher rents or higher-rate-band tax exposure), the early-notify advantage scales linearly with the tax due on the borderline year.

The discovery counterfactual: cost of waiting through HMRC discovery

The calculator's headline benefit is the unprompted floor. The counterfactual is what HMRC could assess if discovery comes first. TMA 1970 section 29 governs discovery assessments; sections 34 and 36 set the time limits.

• Ordinary 4 years (section 34). The default time limit for innocent error.
• Careless 6 years (section 36(1)). The extended limit where the loss of tax is attributable to careless behaviour.
• Deliberate 20 years (section 36(1A)). The far-extended limit where the loss is attributable to deliberate behaviour.
• Offshore innocent-error 12 years (section 36A, inserted by FA 2019). The intermediate limit for offshore innocent error.

HMRC's discovery position drives both the years at risk and the penalty floor. A non-deliberate landlord with 5 years undisclosed who waits for HMRC: 4 years assessable (ordinary), prompted-disclosure 10% floor (Cat 1 UK). The cumulative cost is 4 years of tax plus 4 years of interest plus 10% × 4 years tax in penalty. Disclosing voluntarily: 5 years of tax plus 5 years of interest plus 0% (most recent year) plus 10% (older years) in penalty. The voluntary disclosure may actually pull more years into scope, but at materially lower penalty rates and with the closure-of-exposure benefit on the disclosed period.

For a deliberate landlord, the counterfactual is harsher. 20 years assessable (section 36(1A)); 35% prompted floor; substantial asset-based penalty exposure under FA 2016 Schedule 22 where lost tax exceeds £25,000 in any year. The differential between voluntary disclosure (20% unprompted, scoped to the years the landlord chooses to offer) and HMRC discovery (35% prompted, scoped to whatever HMRC can assess within section 36(1A)) is typically the largest single component of the LPC route's value.

The four triggers that route to specialist counsel

The calculator surfaces a hard routing-to-specialist message rather than a number on four specific fact patterns. Self-service LPC is not the right route in these situations.

Trigger 1: deliberate-and-concealed behaviour

Where the behaviour self-assessment is deliberate and concealed (active steps to hide income, false invoices, third-party-conduit accounts, document destruction), the appropriate route is the Contractual Disclosure Facility under Code of Practice 9, with specialist tax-investigation counsel. CDF confers criminal-prosecution immunity for the conduct described in the formal admission. LPC does not. An LPC disclosure that crystallises deliberate-and-concealed conduct can give HMRC the evidential foundation for a parallel criminal investigation.

Trigger 2: offshore Cat 2 or Cat 3 with pre-30-September-2018 years

Pre-30-September-2018 offshore years engage the Failure-to-Correct overlay under FA 2017 Schedule 18 (200% minimum penalty reducible to 100% on complete unprompted disclosure). The FtC computation sits outside the standalone LPC calculator. The natural route is the Worldwide Disclosure Facility under the DDS umbrella, with specialist counsel input on the FtC overlay calculation.

Trigger 3: HMRC enquiry already open

Where HMRC has opened a section 9A enquiry or issued a section 29 discovery assessment, the disclosure happens within the enquiry framework, not as a standalone LPC notification. The unprompted floor has closed; the engagement is now defensive (managing the enquiry to the lowest defensible position within the prompted-floor bracket) rather than offensive (initiating disclosure on the landlord's terms).

Trigger 4: high total exposure

Where the total estimated liability (tax plus interest plus penalty) is large enough that specialist disclosure counsel adds disproportionate value on the negotiation, the case warrants specialist input. The threshold is judgement-based; £100,000 of total liability is a common practical line, but smaller cases with unusual features (a closing-tax-year argument, a residence-status complication, a complex multi-party structure) can warrant specialist input at lower thresholds.

Interest under TMA 1970 section 86: separate, not mitigated

Interest accrues continuously from each year's due date at Bank of England base rate plus 4 percentage points (the current rate verified at write time against gov.uk's published HMRC interest rates page). Interest is not mitigated by the LPC route. The calculator presents interest as a separate line from the penalty estimate.

For older years, interest can be the largest single line. A landlord with 5 years of unpaid tax on £2,000 per year, at an average effective rate of 7.5%, accrues around £2,800 to £3,200 of cumulative interest by the time of disclosure. Stopping the interest layer requires paying the tax; time-to-pay arrangements under TMA 1970 section 108 do not pause interest, they manage the cash-flow of payment.

HMRC's quality-of-disclosure framework: where within the bracket the penalty lands

The Schedule 41 paragraph 13 floor is the start position. The actual penalty within the floor-to-maximum bracket is set by HMRC in the disclosure-response letter using the quality-of-disclosure framework at CH82400 onwards. Three components:

• Telling. How much the landlord told HMRC about the failure. A complete disclosure covering all rental properties, all years, all income streams, with the full behaviour explanation, scores high.
• Helping. How the landlord assisted HMRC's enquiries. Prompt responses to follow-up correspondence, clear computation work, and a transparent narrative all count.
• Giving access. The documentary and information access provided. Bank statements, agent statements, mortgage records, expense receipts, prior accountant correspondence: full access scores high.

A landlord scoring high on all three components typically settles at or near the floor. A landlord scoring poorly on one or more (incomplete disclosure, slow responses, missing records, evasive narrative) sees the penalty move toward the maximum. The bracket can be wide: for deliberate-not-concealed Cat 1 (20% to 70%), the penalty on £100,000 of tax can range from £20,000 to £70,000 depending on quality-of-disclosure scoring.

How this page sits with the other LPC pages on this site

This page is the calculator-led layer of the LPC pillar. The other LPC pages cover adjacent angles:

• Our LPC orientation page (know about the Let Property Campaign) covers what LPC is and how it fits within HMRC's voluntary-disclosure architecture.
• Our benefits-of-LPC page covers the decision-layer numerical narrative (why disclose at all).
• Our why-voluntary-disclosure-makes-sense page covers the broader decision-theoretic case for moving early.
• Our missed-taxes-rescue page covers the long-history scenario where the omission has run for many years and HMRC is showing risk-flag signals.
• Our digital-disclosure-service page covers the DDS umbrella under which LPC sits, with WDF and CoP9 as adjacent routes.
• Our SA late-filing and late-payment penalties page covers the parallel Schedule 55 and Schedule 56 regime that engages where the landlord has filed a return on time but disclosed inaccurate figures or paid late.

Read this page if your question is "what penalty would I actually pay on my exact facts". Read the orientation page if your question is "what is LPC". Read the benefits page if your question is "why should I bother". Read the rescue page if your question is "HMRC have sent me something, what now". Read the DDS page if your property income has any foreign element.

If you would like a bespoke LPC penalty estimate on your specific facts (with the behaviour-categorisation input, the prompted-or-unprompted status check, the territory categorisation if any property is offshore, and the per-year tax computation including the Section 24 finance-cost interaction), we work with landlords on the disclosure scoping and the negotiation with HMRC on the final settlement. The calculator on this page is a planning starting point; the final number is set in the disclosure-response letter and is materially affected by the quality-of-disclosure framework that we apply on your behalf.