BRITAIN’S 54 billionaires are paying personal taxes on only a fraction of their wealth as experts identify the UK as the world’s first “onshore tax haven”.

The Sunday Times commissioned Grant Thornton, the accountancy firm, to calculate the scale of legal tax avoidance by the country’s wealthiest people. This was after HM Revenue & Customs (HMRC) blocked requests to disclose their aggregate payments under the freedom of information laws.

HMRC refused to release the information on the grounds that it would breach taxpayer confidentiality, although no names would have been made public.

However, publication would have embarrassed Gordon Brown, the chancellor, who will deliver his pre-budget report this week. The Irish authorities release similar figures, which show that 184 people earning more than £1m last year paid no personal taxes.

According to Grant Thornton, the UK billionaires paid income tax totalling just £14.7m on their £126 billion combined fortunes, and only a handful paid any capital gains tax.

At least 32 of the individual billionaires or family groupings are calculated not to have paid any personal taxes on their fortunes, although they are liable for Vat and council tax.

The only figures to have been released by HMRC reveal that the 5,000 Britons earning more than £1m paid direct taxes at an average rate of 34% last year. By comparison, those earning between £500,000 and £1m paid 35.5%, and those earning between £200,000 and £500,000 paid 34.3%.

While middle-class Britons face an increasing tax burden, the country is increasingly regarded as an “onshore tax haven” by the super-rich and their advisers. Mike Warburton, senior tax partner at Grant Thornton, said the overall impact was positive for the British economy because although the billionaires paid low rates of tax, they were important net contributors.

“Some of the world’s wealthiest people are now using London as their base. One of the reasons is that for many of them the UK is effectively a tax haven,” he said. “It means you attract people with enterprise and wealth, but of course some people will see it as very unfair.”

The accountants analysed the published accounts and other records publicly available on the 54 billionaires in The Sunday Times Rich List. This information, although not exhaustive, was sufficient to estimate the likely personal tax liability of the country’s wealthiest. It does not cover the payment of corporate taxes.

It is possible that some of the billionaires voluntarily pay tax they are legally able to avoid. However, of 38 billionaires contacted, none volunteered this information.

The analysis concluded that, in total, the 54 billionaires paid an estimated tax bill totalling £74.5m. James Dyson, the inventor worth £1,050m, contributed the bulk of the income tax paid by the billionaires — £9m of the £14.7m paid by all 54.

He said that although some of his manufacturing plants had moved abroad he continued to believe in paying tax here and “generating wealth” for Britain.

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