Hmrcs use of artificial intelligence – how ai is assessing

Artificial Intelligence is no longer a distant prospect—it’s actively reshaping how HMRC operates. From identifying tax avoidance schemes to spotting anomalies in Self Assessment returns, AI tools are becoming an integral part of the tax authority’s arsenal. Understanding how HMRC uses these technologies is crucial for businesses and individuals across the UK. Here at Severn Accounting, we’ve noticed growing client concerns about AI-driven compliance checks, so we’ve put together this guide to help demystify the process.

How HMRC’s AI Systems Assess Tax Returns

HMRC has invested heavily in artificial intelligence to process the millions of Self Assessment returns filed each year. Their AI systems don’t simply scan for basic errors; they’re designed to identify patterns that deviate from normal behaviour for your industry, income bracket, and filing history.

When you submit a Self Assessment return through the online portal, the data enters HMRC’s data matching systems. These systems automatically compare your declared figures against information received from third parties—employers (via PAYE), banks, building societies, and dividend-paying companies. If your AI flagged return contains significant discrepancies, you’re more likely to face further enquiries.

The threshold for triggering an enquiry varies, but HMRC’s risk-based assessment means that returns showing unusual patterns are given closer scrutiny. For the 2024/25 tax year, if you’re self-employed and declaring income significantly lower than industry benchmarks, or if your expenses appear disproportionately high (for instance, claiming 60% of turnover as expenses when 20% is the sector norm), you’re inviting algorithmic attention.

What Triggers an AI-Powered Investigation?

HMRC’s AI systems monitor several key red flags. Inconsistencies between different parts of your return—such as reporting high profits but minimal tax paid—will set off alerts. Similarly, sudden unexplained changes in your business structure, dramatic shifts in income year-on-year, or claims that don’t align with Companies House filings can trigger automated investigations.

The system also cross-references data from Multiple Indicator Reporting (MIR), which combines various data sources to identify discrepancies. If you’re a director claiming business expenses that don’t correlate with company accounts filed at Companies House, algorithms will spot this mismatch.

Cash-based businesses—restaurants, taxis, retail—face particularly close scrutiny because these sectors are traditionally higher-risk areas for under-reporting. This doesn’t mean you’re automatically suspected of wrongdoing; it simply means HMRC’s AI allocates more processing power to these returns.

The Importance of Accurate Record-Keeping

The best defence against AI-led enquiries is meticulous record-keeping. HMRC’s AI is increasingly sophisticated at identifying genuine business expenses from fabricated ones. If you claim £5,000 in accountancy fees, you should be able to produce invoices. If you claim vehicle expenses, mileage records and fuel receipts should be readily available.

Digital record-keeping has become even more important. HMRC is moving towards mandating digital tax records for businesses, and their AI systems are built to read and analyse digital documents more effectively than paper records. Using cloud-based accounting software or dedicated expense-tracking apps demonstrates a professional approach and reduces errors that might otherwise flag your return.

The key threshold to remember: if you’re self-employed or running a business, keeping records for six years is a legal requirement. HMRC’s AI systems can easily detect when records appear to have been hastily compiled or when expense figures seem suspiciously round.

What Happens if You’re Selected for Enquiry?

Being selected for an HMRC enquiry because of AI-identified discrepancies doesn’t automatically mean there’s a problem. Many enquiries are resolved simply by providing clarification and supporting documentation. However, if your return genuinely contains errors, addressing them early is far better than waiting for HMRC to investigate.

HMRC’s AI doesn’t replace human judgment, but it does determine who gets investigated and how thoroughly. Responding promptly to information notices, providing clear documentation, and being transparent about how you’ve calculated figures will smooth the process considerably.

Taking Control of Your Tax Position

The rise of AI in tax administration isn’t something to fear—it’s simply the landscape we now operate in. By maintaining accurate, organised records and ensuring your returns genuinely reflect your financial position, you’re working with the system rather than against it.

For tailored advice, contact Severn Accounting—we’re here to help.