If HMRC suspects that a taxpayer has committed tax evasion, it may invite them to make a disclosure using the Contractual Disclosure Facility (CDF). These disclosures are made under HMRC's Code of Practice 9 (COP9). Taxpayers can voluntarily request to make a COP9 disclosure.

To enter the COP9 process, the individual must admit that there has been a deliberate failure to report and pay the right amount of tax. Without this admission, HMRC will not accept the taxpayer into CDF.

Many taxpayers entering the COP9 process voluntarily will make an application through the HMRC’s COP9 centre. However, some may choose to make CDF voluntary disclosures outside of the HMRC COP9 centre.

Latest data on HMRC COP9 investigations

In March 2026, we obtained data through a freedom of information (FOI) request confirming that HMRC’S COP9 centre received 127 voluntary applications into CDF during the 2025 calendar year. The data also showed that 21 of these applications were rejected by HMRC.

By contrast, a report previously published by HMRC showed that 306 cases were opened in the year to 31 March 2025. This indicates an increase of almost 15% compared to 2024, when 268 cases were opened. This data suggests that around 65% of taxpayers enter CDF involuntarily, with only 106 doing so through an unprompted application.

What are the benefits of making a voluntary disclosure to HMRC?

There are significant benefits associated with requesting to enter into CDF before being invited, something which will have alluded the current 200 taxpayers subject to the process at HMRC’s behest.

Receiving written correspondence from HMRC containing allegations of tax fraud can be a daunting experience, and the notice requires a response within 60 days. This can be a difficult timeline to meet especially for those without suitable advisers in place. Approaching HMRC on a voluntary basis means that the individual can be in control from day one and has more ability to proactively manage the process.

HMRC is required to consider penalties whenever there are inaccuracies in a taxpayers’ affairs. Where a taxpayer makes a voluntary disclosure through an application for CDF, the minimum penalty applied to tax liabilities associated with deliberate inaccuracies is 20%. However, this minimum penalty is likely to be increased to 35% if the CDF process is followed by an unsolicited invitation from HMRC.

Is HMRC increasing COP9 activity?

In 2025, a report published by the House of Commons public accounts committee found that the cost of tax evasion was likely far higher than HMRC had estimated. The report recommended that HMRC establish a clear strategy for tackling it.

One strategy introduced in late 2025 to tackle tax evasion was the launch of the Strengthened Reward Scheme, which enables individuals to receive up to 15-30% of recovered tax for reporting serious tax avoidance or evasion.

If HMRC is now receiving information through this scheme, it is possible that more taxpayers will be invited into the COP9 process. This will result in a continued upward trend in the number of COP9 cases opened each year, with the personal and financial consequences being most significant for those brought into the regime at HMRC’s request.

For more information and how we can help, please get in touch with Olivia Wiggett or your usual RSM contact.

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