Glossary · UK

What is HMRC Connect?

HMRC's data analytics platform that cross-references income and lifestyle data from multiple sources to identify tax non-compliance.

Full Definition

HMRC Connect is the tax authority's in-house big data and analytics system. It pulls in data from banks, land registries, DVLA, Companies House, social media, digital platforms (see DAC7) and other government departments, then cross-references it against Self Assessment returns and PAYE records to flag discrepancies. Patterns that may trigger a Connect alert include: undeclared rental income where Land Registry shows you own a second property; untaxed business income on social media or trading platforms; lifestyle indicators (expensive cars, holidays, property purchases) that outpace declared income; and large cash transactions. HMRC uses Connect to select cases for compliance checks and investigations. Keeping accurate records and declaring all taxable income is the only reliable defence; penalties for prompted disclosures are lower than those discovered entirely by HMRC.