Tax Revenues 26th November 2015 Tax Investigations Insurance: £800 million more for HMRC, to close the ‘tax gap’. Among the many announcements affecting HMRC and the way it administers the tax system in future years, Chancellor George Osborne has pledged £800 million of funding for additional work to tackle tax evasion and non-compliance. The aim is to raise an additional £7.2 billion of tax over the next 5 years. Taxpayers can expect to see a significant increase in the number of tax investigations undertaken by HMRC. Last year enquiries raised an additional £26.6 billion.