Question to the HM Treasury:

To ask the Chancellor of the Exchequer, if she will make an estimate of the value of uncollected tax in each of the last five financial years.

HM Revenue and Customs (HMRC) estimates the size of the tax gap, which is the difference between the amount of tax that should, in theory, be paid to HMRC, and what is actually paid. The tax gap statistics and details of the estimate methodologies are published annually and are available at: Measuring tax gaps 2025 edition: tax gap estimates for 2023 to 2024 - GOV.UK.

Table 1.3 of the online tables shows the tax gap time series between tax years 2005 to 2006 and 2023 to 2024 in percentage and absolute value terms. In the tax year 2023 to 2024, the tax gap was 5.3% of total theoretical tax liabilities, or £46.8 billion in absolute terms. The tax gap was 5.6% (£46.4 billion) in 2022 to 2023, 5.6% (£41.8 billion) in 2021 to 2022, 5.3% (£34.2 billion) in 2020 to 2021, and 5.8% (£38.5 billion) in 2019 to 2020. The online tables are available at: Measuring tax gaps tables - GOV.UK (www.gov.uk).