WEALTHY homeowners are dodging thousands of pounds in stamp duty by turning their multi-million-pound houses into company assets, according to a confidential study by one of the country’s top estate agents.

Up to two-thirds of homes sold for more than £5m were not officially registered with the Land Registry last year, indicating an almost negligible amount of stamp duty was paid.

This weekend, senior accountants and estate agents admitted that schemes to dodge the tax were now being discreetly marketed to the well-off. Estate agents approached last week by an undercover reporter also offered to help avoid the duty.

The schemes, which are not illegal, can save homebuyers £175,000 on a £5m property. The rate of stamp duty on such “corporate” deals is levied at 0.5% rather than the 4% that other home buyers are paying on property over £500,000.

Since 2001 the amount of stamp duty paid has more than doubled from £2.1 billion to £4.6 billion as Gordon Brown, the chancellor, has refused to increase the thresholds in line with rising house prices.

Lord Oakeshott, a Liberal Democrat Treasury spokesman and leading City figure, called on the chancellor to end exploitation of stamp-duty loopholes by the wealthy. “Brown must end this abuse and cut stamp duty for buyers without expensive City lawyers,” he said.

An internal study by FPD Savills, showed that more than 300 London homes were sold for more than £5m in 2006. However, the agents have established that only 118 were registered with the Land Registry.

The Sunday Times has established that many multi-million-pound mansions are transferred into offshore trusts and companies. It is these that are then sold, not the houses themselves.

The companies — and therefore properties — can change hands many times but these transactions are not recorded at the Land Registry.

Brown has previously tried to close the loophole but accountants and lawyers have devised new ways to exploit it.

Mike Warburton, an accountant at Grant Thornton, said: “It wouldn’t be worth doing for a typical £500,000 house . . . there are costs involved with the schemes, which means it is not worth it for homes worth less than a few million.”

A survey of homes in the Bishops Avenue, one of London’s most exclusive addresses, found that almost 40% of the 83 houses were owned by companies or trusts. Most were registered in the Channel or British Virgin Islands or in Liberia.

Trevor Abrahamson, managing director of Glentree Estates, which specialises in properties in the avenue, said: “It is a process which is becoming more and more common.” Additional reporting: Gareth Walsh and Isabel Oakeshott

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