UK · Updated 2026-07-06

HMRC whistleblowing: how to report tax fraud in 2026

By Confidly editorial · Published 2026-07-06

The main HMRC building in London with columns and a flag

HM Revenue and Customs handles roughly 100,000 whistleblower tip-offs a year, and that number keeps climbing. Most of them are made anonymously by employees, ex-employees, spouses, and competitors who see something they know is wrong: undeclared cash, false invoices, disguised remuneration, VAT carousels, offshore secrecy. A smaller and growing share come from finance and payroll staff who spot the problem inside the company and want it fixed without their name attached. This guide covers both routes. It sets out how the HMRC whistleblowing regime actually works in 2026, what legal protection a UK worker gets, whether they can be paid, and where an internal channel fits before HMRC ever sees a report.

Direct answer

HMRC whistleblowing lets any person report suspected tax fraud, evasion, or serious avoidance to HM Revenue and Customs, either through the Fraud Hotline (0800 788 887), the online form on gov.uk, or by post to the HMRC Fraud Hotline in Cardiff. Reports can be made anonymously. Where the reporter is a UK worker making a “protected disclosure” about their employer’s tax affairs, the Public Interest Disclosure Act 1998 (PIDA) protects them from dismissal or detriment, because HMRC is a prescribed regulator. Since April 2026 HMRC also operates a new reward scheme for informants whose intelligence leads to recovered tax, modelled on the US IRS approach. A well-run internal channel resolves most of these matters before external reporting is needed, and evidence that one exists strengthens the firm’s position with HMRC if it ever becomes an inquiry.

Who HMRC’s whistleblowing channel is for

HMRC’s channel is deliberately broad. It accepts information from anyone about anyone: a payroll clerk about their employer, a landlord’s tenant about undeclared rent, a former director about a live scheme, a business rival about a competitor. HMRC does not ask the reporter to prove anything, only to describe what they saw, when, where, and who was involved. The Fraud Investigation Service decides whether the tip is actionable and, if so, whether it fits a civil (COP9) or criminal route.

Three categories of reporter dominate:

Employees and ex-employees. Finance, payroll, tax, and internal audit staff account for the majority of employer-related tips. They see the underlying transactions and know how the numbers are constructed. When they report their employer, PIDA protection is in play, and their exposure is the reason most reports arrive anonymously.

Advisers and intermediaries. Accountants, solicitors, and tax advisers occasionally report clients whose behaviour crossed a line. Professional privilege limits what they can say without client consent, but there are recognised routes where the adviser reasonably suspects a criminal offence, including a Suspicious Activity Report to the National Crime Agency that HMRC receives via the SAR regime.

Third parties. Landlords, ex-partners, competitors, and members of the public with direct knowledge of an undeclared income stream, hidden asset, or contrived arrangement. Their intelligence is less structured than an insider’s but often supplies the address, name, and lifestyle indicators that trigger a compliance check.

What counts as a reportable HMRC concern

Not every complaint about a company’s tax bill is a whistleblowing matter. HMRC’s fraud-hotline path is for suspicions of criminal or reckless behaviour, not for policy disagreement.

The concerns HMRC wants to hear about include:

Deliberate under-declaration of income (cash sales kept off the books, unrecorded rent, undeclared self-employment).
False expenses or fabricated invoices (goods or services never supplied, mark-ups to related parties designed to strip profit).
VAT fraud, including missing-trader and carousel schemes.
Disguised remuneration, contractor-loan schemes, and off-payroll arrangements that ignore IR35.
Hidden assets, undeclared offshore accounts, and beneficial-ownership structures used to conceal income.
Employer national insurance and PAYE errors that look deliberate (routine payroll mistakes go through the normal correction route, not the hotline).
Excise fraud (tobacco, alcohol, hydrocarbon oils) and smuggling.
Money laundering that is layered through what looks like a legitimate trade.

Matters that do not belong on the hotline include disagreements about how much tax someone should pay, complaints about HMRC service quality (those go through the Adjudicator’s Office), and personal grievances about a colleague that have no tax dimension.

For a worker considering an internal or external report, the test to keep in mind is the PIDA test: does the disclosure tend to show a criminal offence, a breach of a legal obligation, a miscarriage of justice, a risk to health and safety, environmental damage, or a deliberate concealment of any of those? Tax fraud sits inside the first two.

A close-up of tax documents on a desk

Photo by Kelly Sikkema on Unsplash

How to report to HMRC in practice

HMRC publishes four channels. Any of them is valid. The choice depends on how much detail the reporter wants to share and whether they need to stay anonymous.

The online form on gov.uk. The default. The form takes structured information (subject, time period, place, evidence), attaches free-text detail, and lets the reporter withhold personal details. It is the fastest route for a first report and generates a case reference.

The Fraud Hotline: 0800 788 887. Open Monday to Friday, staffed by trained officers who can take a report by phone. Callers do not have to give their name. The line is useful when the reporter wants to describe something that is hard to convey in writing, or when they are worried about a paper trail.

By post. Reports can be sent to HMRC Fraud Hotline, Cardiff, CF14 5ZN. Slower, but occasionally the right choice when the reporter wants to enclose paper evidence and record delivery.

Via a professional intermediary. Solicitors and accountants can report on their client’s behalf under legal privilege where the client consents. Advisers who suspect their own client of a criminal offence have a separate route through the SAR regime.

Once HMRC has the report, the Fraud Investigation Service triages it. Some tips go straight into an existing investigation. Others become intelligence that sits in HMRC’s Connect system for cross-matching against later filings. A tip on its own rarely opens an inquiry: it becomes an inquiry when it correlates with data HMRC already holds, at which point the reporter is asked (through the case reference) whether they can provide further detail.

Timings vary. HMRC does not commit to a response window, and by policy does not tell the reporter what was done with their information (to protect both the reporter and the taxpayer). A prosecution can take three to seven years from the original tip; a civil recovery is often faster.

Anonymity, confidentiality, and what HMRC will and will not confirm

The most common question from a would-be reporter is whether HMRC will keep them anonymous. The answer has three parts.

HMRC accepts anonymous tips. The reporter does not have to give their name at all. An anonymous tip is investigated on its own merits.

Where the reporter does give their name, HMRC treats it as confidential. Officers will not confirm the reporter’s identity to the taxpayer under investigation, and will structure any subsequent questions to the taxpayer so that the source is not inferable. HMRC’s Charter commits to this in general terms; internal guidance sets out how to phrase enquiries.

The one situation where identity can surface is criminal court. If the case goes to prosecution and the reporter’s evidence is needed as a witness, disclosure rules can require identification. In practice HMRC often prosecutes on documentary evidence alone and the informant never appears. Where a court appearance is genuinely on the horizon, HMRC tells the reporter well in advance and considers protective measures.

For a worker reporting their employer, confidentiality inside HMRC is only half the risk picture. The other half is what happens inside the workplace: retaliation, exclusion, being frozen out of promotions. That risk is addressed not by HMRC’s channel but by the Public Interest Disclosure Act.

PIDA protection for HMRC reports

The Public Interest Disclosure Act 1998, as inserted into the Employment Rights Act, is the UK’s whistleblower-protection statute. A UK worker who makes a qualifying disclosure to the right recipient in the right way is protected from dismissal, from selection for redundancy on that ground, and from any other detriment linked to the disclosure. HMRC is a “prescribed person” for tax matters, so an external disclosure straight to HMRC is protected on the same footing as an internal disclosure to the employer.

For the protection to bite, three things need to be true:

The worker must have a reasonable belief that the information tends to show one of the six categories (criminal offence, breach of legal obligation, miscarriage of justice, health-and-safety risk, environmental damage, or concealment of any of those). Belief in tax fraud clears the first two.

The disclosure must be made in the public interest. A dispute purely about the worker’s own pay is not enough; a systemic scheme that harms revenue clearly is.

The recipient must be permitted. HMRC is a prescribed regulator for “income tax, corporation tax, capital gains tax, national insurance contributions, VAT, insurance premium tax, excise duties and customs duties”. Reporting there is protected by default. Reporting to another regulator on a matter outside its remit is not.

If the employer dismisses, disciplines, or otherwise punishes a protected reporter, the worker can bring a claim in the Employment Tribunal without the usual two-year qualifying period. Compensation is uncapped, and Tribunals have been willing to award six-figure sums where the retaliation was clear.

For firms, the PIDA exposure is a business-continuity issue as much as a legal one. Losing a whistleblowing Tribunal is separately reportable to the FCA where the employer is regulated, and the reputational damage tends to dwarf the underlying tax exposure.

Do HMRC whistleblowers get paid?

For most of HMRC’s history, the answer was: only ex gratia. The department could make small payments (a few hundred to a few thousand pounds) where a tip led directly to recovery, but there was no scheme and no legal right. Successive Public Accounts Committee reports urged HMRC to move closer to the US IRS model, which pays 15% to 30% of collected proceeds to informants.

From April 2026 a new informant-reward regime, announced at the 2025 Autumn Statement, applies to tips leading to recovered tax of £100,000 or more. The scheme is capped and administered by a dedicated informant unit inside the Fraud Investigation Service. The percentage is expected to sit in the 10% to 25% band, below the US regime but a substantive move from ex-gratia.

Practical implications:

Small tips (undeclared cash at a takeaway, an unregistered second job) fall below the threshold and do not qualify.
Tips against employers with material undeclared liabilities do qualify. Payroll and finance staff with six- or seven-figure visibility are the intended reporters.
Anonymity and reward are not fully compatible. Payment requires identity verification and a bank account, so a reporter who wants both typically reports anonymously first, then engages a legal representative when the case matures.

The change strengthens the incentive for a disgruntled ex-employee to go straight to HMRC rather than raise the concern internally. A well-run internal channel that resolves the underlying issue is the mitigation.

Where the internal channel fits

By the time an HMRC tip is made, the firm has usually missed at least one internal opportunity to fix the issue. When we ask a payroll clerk why they went straight to HMRC, the answer is almost always one of four: they did raise it and got shut down, they were scared their name would come out, the internal route asked for an email address and they did not trust it, or nobody ever told them there was an internal route.

An internal channel that reliably catches these concerns has four properties:

It is genuinely anonymous. No email required, no IP address logged, no cookie or fingerprint captured. If the reporter can be identified from the form alone, staff learn to distrust it and use HMRC instead. Confidly’s public intake form issues a server-side case code and a reporter-only secret; no personal identifier is stored.

It is triaged by a named case handler with real authority. Tax matters cross legal, finance, and compliance. The internal owner needs the seniority to escalate to the audit committee if the matter is material. Nobody reports a tax scheme to a channel run by the person who signed off on it.

The 7-day acknowledgement and 3-month feedback are enforced. These are EU-directive numbers rather than PIDA numbers, but the discipline (the reporter hears something back on a defined clock) is what keeps them engaged internally. A reporter who has heard nothing after two months assumes the tip is being buried and picks up the hotline.

It is separately audited. The audit trail has to be tamper-evident and available to the auditor if the tax authority ever inquires. HMRC’s Framework for Cooperative Compliance credits firms that can demonstrate they self-identify and self-report; an audit-ready internal channel is the mechanism.

The board test is whether a payroll clerk with a concern about disguised remuneration would use the channel or the hotline. If the answer is the hotline, the channel is broken.

A compliance team working at desks in an open office

Photo by Israel Andrade on Unsplash

Common misunderstandings

“HMRC whistleblowing is the same as the FCA regime.” No. The FCA runs its own rules in SYSC 18 for regulated financial firms. HMRC’s regime is a tax-authority intelligence channel with no equivalent Handbook. A firm subject to both needs arrangements that satisfy each. See our FCA whistleblowing guide for the SYSC 18 detail.

“An anonymous report is not evidence.” HMRC treats anonymous tips as intelligence and cross-matches them against Connect data. A single tip rarely opens an inquiry on its own; combined with a return that looks off, an unusual VAT profile, or a lifestyle inconsistency, it routinely does.

“Reporting is protected only if I report internally first.” No. HMRC is a prescribed person, so an external report to HMRC is protected by PIDA on the same footing as internal reporting. Going internal first is good hygiene, not a legal prerequisite.

“Small businesses are below HMRC’s radar.” They are not. Cash-heavy sectors (takeaways, taxi companies, hospitality, small landlords) attract a disproportionate share of tip-offs and, since the risk-based Connect system was upgraded, a disproportionate share of the follow-through.

FAQ

Is HMRC whistleblowing the same as reporting to the FCA? No. HMRC is the UK’s tax authority; its whistleblowing route is a fraud-intelligence channel for suspected tax offences. The FCA is the financial-conduct regulator with its own whistleblowing rules in SYSC 18 for banks, insurers, and large investment firms. A regulated firm can be reported to both on different matters. Reporters use the FCA channel for conduct and prudential breaches, the HMRC channel for tax fraud.

Can I really report to HMRC anonymously? Yes. The online form and the Fraud Hotline both accept anonymous tips. HMRC investigates the substance; the reporter does not have to give their name. If the reporter does share their name it is treated as confidential intelligence and is not disclosed to the taxpayer, subject only to court disclosure rules if a case goes to prosecution.

Am I legally protected if I report my employer to HMRC? Generally yes. Under the Public Interest Disclosure Act, HMRC is a “prescribed person” for tax matters, so an external report to HMRC that meets the qualifying-disclosure test is protected from dismissal or detriment. Compensation in the Employment Tribunal is uncapped, and there is no minimum service requirement to bring a claim.

Will HMRC pay me for a tip? For tips leading to recovered tax of £100,000 or more, HMRC’s new informant reward regime (in force from April 2026) can pay a proportion (expected 10% to 25%) of the recovered amount. Below that threshold, ex-gratia payments remain discretionary and modest. The reward regime is materially below US IRS levels but marks a real change from the previous ex-gratia baseline.

How long does an HMRC investigation take? HMRC does not commit to a response window and does not routinely update reporters on progress. A civil recovery under COP9 can take 12 to 24 months. A criminal prosecution typically takes three to seven years from the original tip to verdict, with most of that time in Fraud Investigation Service work-up before charges are laid.

Does an internal channel replace the HMRC route? No, and it should not try to. An internal channel is the first stop for a worker who spots a problem, gives the firm a chance to fix it, and is a mitigation the firm can point to in any subsequent HMRC engagement. The worker retains the right to go to HMRC directly at any time. A channel that discourages external reporting, or that appears to, is a PIDA problem in its own right.