CoP9 and the Contractual Disclosure Facility: HMRC Tax Fraud Investigation for Landlords

The arrival of a Code of Practice 9 letter from HMRC is one of the most serious events a landlord can face. It signals that HMRC has formed a suspicion of tax fraud and is offering the taxpayer a civil-resolution route under the Contractual Disclosure Facility. The 60-day acceptance window is short, the immunity that flows from acceptance is real but narrowly scoped, and the consequences of mis-handling the response can include criminal prosecution.

This page explains what CoP9 is, what the Contractual Disclosure Facility is, what the 60-day acceptance mechanic looks like in practice, what the Outline Disclosure and Disclosure Report sequence requires, and how CoP9 sits alongside the other HMRC disclosure routes (the Let Property Campaign, the Worldwide Disclosure Facility, and the general Digital Disclosure Service). It is written as orientation for landlords and accountants; CoP9 representation itself is specialist territory and should be referred to tax-investigations counsel.

What CoP9 is

HMRC Code of Practice 9 is HMRC's published code under which the Contractual Disclosure Facility (CDF) operates. The current edition is CoP9 (2014), with editorial republishing since. CoP9 is issued by HMRC where it has formed a view that a taxpayer is involved in tax fraud and where HMRC is willing to resolve the matter civilly rather than by criminal prosecution.

CoP9 is not statutory. There is no specific Act or Schedule that creates the CDF. Instead, CoP9 is an undertaking by HMRC, set out in published form, that conditions HMRC's choice between civil and criminal proceedings. The legal basis for HMRC's prosecution discretion sits in the general criminal-investigation framework and (for certain offences) in specific statutory powers, but the operational gateway between civil and criminal handling is CoP9. HMRC's Enquiry Manual at EM6000 onwards sets out the internal handling guidance for civil-fraud investigations.

The CDF as a contractual route

The Contractual Disclosure Facility is the contract through which the taxpayer accepts HMRC's CoP9 offer. By signing the CDF, the taxpayer commits to making a full disclosure of tax fraud (in the Outline Disclosure and Disclosure Report) in exchange for HMRC's commitment not to pursue criminal prosecution on the matters disclosed.

The CDF is a contract in the ordinary sense: there is offer (HMRC's CoP9 letter), acceptance (the signed CDF document plus Outline Disclosure within 60 days), consideration (the taxpayer's full disclosure on one side, HMRC's prosecution-immunity commitment on the other), and intention to create legal relations. The contractual framing matters because the immunity is contingent on the taxpayer's performance: false statements, material non-disclosure, or withholding evidence revoke immunity and restore HMRC's full prosecution discretion.

The 60-day acceptance window

HMRC's CoP9 letter triggers a fixed 60-day window within which the taxpayer must:

• Sign the CDF acceptance document.
• Submit the Outline Disclosure summarising the tax fraud.

The 60 days is not extendable on the face of CoP9. In practice HMRC has been willing to extend by a short period (typically a further 30 days) where the taxpayer is actively engaging with specialist counsel and the delay is unavoidable, but this is HMRC discretion and should not be assumed.

If the 60-day window passes without acceptance, HMRC retains its full prosecution discretion. The taxpayer may still seek to engage with HMRC, but the CDF offer has expired and any future engagement is on HMRC's terms rather than within the CoP9 framework. Practically, missing the window is a serious negative; the taxpayer faces the same fraud investigation but without the CDF immunity backstop.

The Outline Disclosure

The Outline Disclosure is a short document submitted with the CDF acceptance. It is not the full account of the fraud; it is the summary that defines the scope of the CDF immunity. The Outline Disclosure typically covers:

• The nature of the tax fraud (for example, deliberate omission of rental income, false repair claims, fabricated capital allowances).
• The years of assessment involved.
• The approximate tax loss (with the precise calculation to come in the Disclosure Report).
• Any other persons connected with the fraud (other taxpayers, advisers, intermediaries).

The Outline Disclosure must be honest and complete on the matters it covers. Material omission at the Outline Disclosure stage is one of the most common ways CDF immunity is later revoked. The drafting discipline is to disclose fully on the matters known to be in scope, and to disclose with appropriate hedging on matters under investigation but not yet fully understood.

The Disclosure Report

The Disclosure Report is the full account of the tax fraud, submitted on a longer timeline by agreement with HMRC (typically 6 to 12 months from CDF acceptance). The Report includes:

• The detailed calculation of tax loss, year by year, with full supporting evidence.
• The behavioural analysis explaining how the fraud arose, who knew what, and when.
• The Schedule 24 FA 2007 or Schedule 41 FA 2008 penalty band representations.
• The mitigation arguments on quality of disclosure (telling, helping, giving access).
• Identification of any third parties involved.
• Representations on suspension (Schedule 24 paragraph 14, careless only).

The Report is reviewed by HMRC's Fraud Investigation Service. The Service may seek further information, may interview the taxpayer (under caution where appropriate), and may engage in extended fact-finding before reaching its final position on the tax loss, penalties and interest.

The scope and limits of CDF immunity

Three structural points on the immunity matter operationally. First, the immunity is limited to matters disclosed in the Outline Disclosure and the Disclosure Report. Non-disclosed matters are outside the immunity and remain subject to HMRC's full prosecution discretion. Second, false statements in CDF documents revoke immunity and expose the taxpayer to criminal investigation including for the disclosed conduct. Third, the immunity does not extend to other persons named in the disclosure: their position is governed by HMRC's separate engagement with them.

The operational discipline: disclose fully on everything known to be in scope, hedge appropriately on matters under investigation, and never make a statement to HMRC that is materially inaccurate. The cost of an inaccurate disclosure is not merely a higher penalty band; it is potential criminal prosecution for the very conduct the taxpayer was trying to resolve civilly.

CoP9 vs LPC vs WDF vs DDS: the route distinction

HMRC's disclosure architecture for landlord-facing matters has four main routes, and choosing the right route is the most consequential early decision in any disclosure case.

• Let Property Campaign (LPC). Residential-rental disclosure route for UK landlords with undisclosed rental income. Operates within the Schedule 41 FA 2008 framework. Suitable for careless or innocent-error cases. No criminal-immunity component. Three-step process: notify, disclose within 90 days, pay. See our coverage of the penalty regime for undeclared rental income for the LPC context.
• Worldwide Disclosure Facility (WDF). Offshore disclosure route for any person with undisclosed UK tax liability connected to offshore income, gains or assets. 90-day disclosure timeline (extendable to 180 for complex cases). No criminal-immunity component. HMRC retains prosecution discretion.
• Digital Disclosure Service (DDS). General voluntary disclosure for UK-only non-rental matters not covered by LPC. Same operational principles as LPC: notify, disclose, pay. No criminal-immunity component.
• CoP9 / CDF. HMRC-initiated civil-fraud investigation track. Criminal-immunity component (limited to matters disclosed). Suitable for deliberate-behaviour cases with criminal-prosecution exposure. 60-day acceptance window. Specialist representation effectively required.

The decision tree: if the conduct is innocent error or careless, and the income type is residential rental, LPC is the route. If careless and offshore, WDF. If careless and UK non-rental, DDS. If deliberate with criminal exposure, CoP9 / CDF, taken with specialist counsel. The boundary between careless-and-LPC and deliberate-and-CoP9 is the single most important early-case judgement, because once a CoP9 letter has been issued by HMRC, the LPC route is closed.

The disclosure-mitigation framework that runs across all four routes is set out in HMRC's Compliance Handbook at CH150000 onwards. The mechanics are similar across routes (telling, helping, giving access) but the route choice determines which behaviour bands and which time limits apply, and whether criminal-prosecution immunity is on the table.

Taxpayer-initiated CDF request

The CoP9 / CDF framework is normally HMRC-initiated: HMRC has formed a fraud suspicion and is offering the CDF. There is also a taxpayer-initiated route where a taxpayer with deliberate-behaviour exposure approaches HMRC seeking to be put under CoP9 in order to secure the criminal-immunity protection.

Taxpayer-initiated CDF requests are made through specialist counsel to HMRC's Fraud Investigation Service. The taxpayer's representations include an outline of the suspected fraud, the years involved, the approximate tax loss, and the reasons for seeking CDF rather than LPC / WDF / DDS. HMRC reviews and decides whether to issue a CoP9 letter (which then triggers the standard 60-day acceptance window and CDF mechanics).

The taxpayer-initiated route is used where the taxpayer's position is sufficiently deliberate that LPC / WDF / DDS would not provide criminal-prosecution protection but the taxpayer wants to come forward proactively before HMRC discovery. It is a serious step that should be considered only with specialist counsel.

CoP9 vs CoP8 vs CoP10: HMRC's investigation code framework

HMRC's investigation framework uses three published codes, and orientation between them is important. Code of Practice 8 (CoP8) is HMRC's published code for serious tax-avoidance investigations where fraud is not suspected. It is the route HMRC uses for complex avoidance arrangements, marketed schemes, and high-value but technically defensible positions. CoP8 does not carry a CDF / criminal-immunity component because there is no fraud-prosecution exposure to immunise against.

Code of Practice 10 (CoP10) is HMRC's published code for information requests in cases where neither fraud nor formal avoidance is suspected but HMRC needs information from a third party. CoP10 is procedural and does not engage civil-resolution mechanics in the way CoP9 does.

Practically: a CoP8 letter signals serious tax-avoidance investigation; a CoP9 letter signals suspected tax fraud and the CDF offer; a CoP10 letter signals an information request without underlying investigation. The codes can sometimes flip mid-engagement (HMRC moves from CoP8 to CoP9 if avoidance investigation surfaces fraud evidence), and the move carries meaningful procedural implications.

HMRC's Fraud Investigation Service

The Fraud Investigation Service (FIS) is HMRC's specialist directorate handling civil and criminal fraud cases. CoP9 / CDF cases are managed by FIS officers rather than ordinary compliance officers. The substantive consequence is two-fold: FIS officers are better-resourced and more specialist than ordinary HMRC officers, and the procedural rigour applied to the Disclosure Report is correspondingly higher.

FIS officers typically conduct an in-person interview as part of the Disclosure Report process. The interview is generally not under caution (the CDF acceptance shifts the resolution into the civil track), but inconsistencies between the Disclosure Report and the interview can revoke the CDF immunity. Specialist counsel will normally prepare the taxpayer extensively for the FIS interview and may be present during it.

The FIS also retains a parallel criminal-investigation function. Cases that fail CDF (rejected, late, or revoked) can be transferred from the civil to the criminal arm of FIS. Within the criminal arm, the case is conducted under the Police and Criminal Evidence Act 1984 framework and ultimately referred to the Crown Prosecution Service for charging decisions. HMRC's published prosecution policy sits at HMRC Criminal Investigation Policy.

Anti-money-laundering reporting interaction

Where a landlord engages an accountant or solicitor in disclosure work, the adviser is a regulated person under the Money Laundering Regulations 2017 and may have a suspicious-activity-report obligation under section 330 of the Proceeds of Crime Act 2002. The interaction with CoP9 is nuanced: an adviser advising on a CoP9 / CDF engagement that the client has accepted is generally working within a contractual route to civil resolution, but the underlying conduct (the tax fraud) is a predicate offence for money-laundering purposes.

The practical position: advisers engaged on CDF representation will typically have made (or will make) a defensive SAR on the underlying fraud at the point of engagement. The SAR does not break privilege and does not interfere with the CDF process, but it does generate a record. Landlords engaging advisers on CoP9 / CDF should expect this to happen as standard adviser-discipline rather than as anything specific to their case.

Worked scenario: receiving a CoP9 letter on undeclared offshore rental

Background. A higher-rate landlord owns rental property in Spain held through a UK-based trust structure (set up in 2014). The rental income has been deliberately omitted from UK self-assessment returns for the 2014/15 to 2024/25 tax years on the basis that "the Spanish tax authority deals with Spanish income". The landlord has used fabricated repair invoices to extract funds from the trust.

Trigger. HMRC opens a fraud investigation following a CRS data match from Spain plus a SAR from the trust's UK accountant. HMRC issues a CoP9 letter offering CDF.

Day 1-7. The landlord engages specialist tax-investigations counsel. Counsel reviews the CoP9 letter, the trust documentation, and the underlying records. The route choice is straightforward: the deliberate-behaviour and active-concealment elements (fabricated invoices) put the case clearly in CoP9 territory rather than WDF or LPC. CDF acceptance is the right move.

Day 8-45. Counsel and the landlord draft the Outline Disclosure. The Outline covers: deliberate omission of Spanish rental income for tax years 2014/15 to 2024/25; approximate tax loss of £180,000 across the 11 years; fabricated repair invoices used to extract approximately £50,000; the trust structure used to hold the property; the involvement of an accountant who prepared the (false) accounts. The Outline is hedged on the precise tax-loss calculation pending the full Disclosure Report.

Day 50-60. The CDF acceptance and Outline Disclosure are submitted. HMRC acknowledges and starts the Disclosure Report process. The agreed timeline for the Disclosure Report is 9 months.

Months 3-9 of disclosure. Counsel and Property Tax Partners (engaged on the substantive tax-technical position) work through the year-by-year calculation. Spain is Category 1 for Schedule 24 purposes (CRS full information exchange), so the offshore uplift is not engaged on penalty bands. But Schedule 24 deliberate-and-concealed bands apply: 100 per cent maximum, mitigation to 30 per cent unprompted or 50 per cent prompted. With prompted disclosure (HMRC opened the investigation), the floor is 50 per cent. The negotiated penalty lands at 60 per cent of the £180,000 tax loss, namely £108,000. Schedule 21 FA 2015 asset-move penalty does not apply (no inter-territory asset moves).

Outcome. Total settlement: £180,000 tax + £108,000 penalty + £45,000 interest = £333,000. Plus counsel and tax-technical fees of approximately £40,000. No criminal prosecution (CDF immunity holds because the disclosure was full and honest). The landlord retains the trust structure but switches to UK-resident-trustee + UK-tax-compliance going forward.

The scenario is composite and anonymised but illustrative of how CoP9 / CDF works in landlord practice. The 60-day Outline Disclosure pressure is real, the FIS review is rigorous, and the penalty exposure is significant. Compared to the alternative (criminal prosecution under section 106A TMA 1970 or general fraud legislation, with potential imprisonment), the civil resolution is materially better, but it is not cheap.

How CoP9 sits alongside other landlord penalty regimes

CoP9 / CDF is a procedural framework for resolving fraud cases civilly. It does not displace the underlying penalty regimes: Schedule 24 FA 2007 inaccuracy penalties still apply where the fraud involves inaccurate returns; Schedule 41 FA 2008 failure-to-notify penalties apply where the fraud involves failure to register. The penalty negotiation happens within the Disclosure Report process, with disclosure-mitigation arguments running on quality-of-disclosure principles.

The discovery time limits under TMA 1970 sections 29, 34, 36 and 36A apply: deliberate behaviour engages the 20-year section 36(1A) limit, so HMRC can assess up to 20 years back in CoP9 cases. Offshore matters engage the 12-year section 36A limit independently of behaviour, and where the offshore matter is deliberate, the 20-year limit operates.

If you have received a CoP9 letter from HMRC, the first action is to engage specialist tax-investigations counsel within the first 7 days. The substantive tax-position work, including the eventual Disclosure Report content and penalty representations, is where Property Tax Partners can contribute as the underlying tax-technical adviser. Use the form at the foot of the page to discuss the substantive position.