Committee publication · Correspondence · 30 June 2026

Correspondence from the First Permanent Secretary and Chief Executive of HM Revenue and Customs on Measuring Tax Gaps 2026, dated 23 June 2026

From: Treasury Committee

Inquiry: Work of HM Revenue and Customs

Summary

John-Paul Marks, HMRC's Chief Executive, writes to Treasury Committee Chair Dame Meg Hillier transmitting the 2026 Measuring Tax Gaps report. The UK tax gap for 2024-25 is estimated at 6.4% (£59.2 billion). HMRC notes the figure is down from 7.5% since 2005-06, highlights record £48 billion compliance yield in 2024-25, and outlines investment of £1.7 billion and recruitment of 5,500 staff to tackle non-compliance.

Key findings

  • Provisional UK tax gap for 2024-25: 6.4% of theoretical liabilities, equivalent to £59.2 billion
  • Tax gap has declined from 7.5% since measurement began in 2005-06; broadly stable in recent years as percentage of receipts
  • Small business non-compliance accounts for 60% of total tax gap; large business tax gap on long-term downward trend
  • HMRC collected record £48 billion compliance yield in 2024-25; targeting £50.4 billion in 2025-26, rising to over £60 billion by 2029-30
  • Government investment of £1.7 billion in HMRC technology, data, and people; 5,500 staff recruitment ahead of schedule with 2,300+ already hired

Tone

Factual

Topics

public-financetax-compliancerevenue-administration

Key actors

John-Paul Marks, Dame Meg Hillier, HM Revenue and Customs (HMRC), UK Government

Notable line

The tax gap is down from 7.5 per cent since measurement began in 2005-06.

Key Quotes

The report estimates that the provisional tax gap is 6.4%, or £59.2 billion, of total theoretical liabilities in 2024-25.
John-Paul Marks · Transmitting the 2026 tax gap measurement report to the Treasury Committee
HMRC is internationally recognised as a leader in the field of estimating tax gaps, and we are the only revenue authority in the world that measures and publishes the tax gap to this extent every year.
HMRC (Annex A statement) · Explaining HMRC's role in tax gap measurement
The small business tax gap is mostly due to relatively small sums amplified across a population of more than five million businesses; some of this is error, some is careless and some is more deliberate behaviour.
HMRC (Annex A statement) · Analysing the composition and drivers of small business non-compliance
The large business tax gap remains low – with large business unpaid tax as a share of the overall tax gap on a long-term downward trend.
HMRC (Annex A statement) · Comparing large and small business compliance patterns
Our compliance interventions are bringing in more than ever before: in 2024-25, we collected and protected a record £48 billion in compliance yield.
HMRC (Annex A statement) · Describing recent compliance performance and outcomes
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Source · parliament.uk record ↗