Question to the HM Treasury:

To ask Mr Chancellor of the Exchequer, what estimate he has made of the annual cost to the public purse of tax avoidance and tax evasion.

HMRC publish estimates of the tax gap in Measuring Tax Gaps each year. The 2014 edition (published on 16 October 2014) presents a time series of tax gaps from 2005-06 to 2012-13, which can be found at the following link:

https://www.gov.uk/government/statistics/measuring-tax-gaps

Measuring Tax Gaps includes an illustrative breakdown of the tax gap by behaviour, including avoidance and evasion. In 2012-13 avoidance was estimated to cost the exchequer £3.1 billion, and evasion to cost £4.1 billion.