The former IT head at Vodafone UK has been hired as HMRC's chief digital and information officer (CIO) responsible for the tax department's £500m IT operation.

Mark Dearnley will take up the £180,000 job in October, and will head up the £500m-a-year IT operation that supports 45m individuals, 4.8m businesses and 65,000 HMRC employees.

Dearnley will be responsible for implementing HMRC's £200m digitisation programme and leading the rollout of a fully online service for taxpayers.

While CIO at Vodafone UK, Dearnley overhauled the mobile operator's business-critical information systems, restructured the IT operating model and introduced cloud-based technologies. He was also named Oracle Global Business Unit CIO of the Year in 2012.

Dearnley has spent ten years working internationally in the telecoms sector and previously held senior IT roles at Cable & Wireless and Boots.

Dearnley said: 'I have spent my entire career in the private sector, mostly in customer-facing businesses. But no private business in the UK can match the customer base, scale or complexity of HMRC, which makes this role irresistible. I am thrilled to have been appointed and can't wait to get started.'

Treasury secretary David Gauke said: 'It is an indication of the scale and seriousness of the government's digital ambition that one of the UK's most experienced CIOs is leaving the private sector to take on this major role.'