High earners could be pursued with new vigour by the tax authorities as specialist teams were set up this week to examine the financial affairs of some of the UK’s most wealthy individuals.

The new “high net worth unit” will identify the 5,000 wealthiest taxpayers in the UK and conduct thorough reviews of their financial dealings and assets.

Inspectors are expected to pay particularly close attention to complex property and shares transactions, particularly when opaque structures, such as offshore trusts and companies, have been used.

HM Revenue & Customs (HMRC) says the intention is to offer wealthy individuals a more personal, tailored and proactive service.

Each person who comes under the scrutiny of the new teams will be assigned their own contact who will be experienced in the kinds of complex tax structures used by wealthy people.

“We will be engaging with these customers and their agents to help them ensure they pay the right amount of tax,” explains a Revenue spokesman. “We will be taking a holistic approach, looking at all aspects of the individual’s tax affairs.”

HMRC claims the new specialist division will help it better understand the financial affairs of high earners and make it easier for them to submit an accurate tax return.

But accountants say the “better” service could translate into a bigger tax bill for clients.

“There will be a smaller, very specific team who will really concentrate on the tax affairs of particular high net worth individuals,” says Sue Holmes, head of tax investigations at Smith & Williamson, the accountancy firm. “Clients are concerned they are going to come under the microscope more than ever.”

Previously HMRC’s “complex personal tax teams” dealt with around 42,000 wealthy UK-domiciled people. So the fact that just 10 per cent or so of these people are being transferred to a specialist team signals a much closer interest in their tax status.

HMRC says the new unit will be made up of around 500 staff, so each person will be dealing with just 10 wealthy taxpayers. It has not specified the level of wealth for individuals to come under the new teams but accountants suggest it could be £10m-plus.

Holmes expects that anyone likely to be targeted will be informed over the next couple of months. She says the selected individuals are likely to receive a detailed questionnaire asking about their assets and dealings, which will be used to obtain information that is not available in the public domain.

“I expect there will be some fairly probing questions that are trying to establish the extent of the person’s wealth and their connections offshore,” she says. “I don’t think the Revenue will wait for the next set of tax returns to come in.”

The new inspectors are also likely to sift through publicly available information such as property sales databases, land registry titles and shareholder registers, as well as records held by overseas revenue authorities and other federal agencies to glean information about their clients.

David Kilshaw, head of private client advisory at KPMG in the UK, believes that while the establishment of the new teams could trigger an initial reaction of “fear, fear, fear” in some clients, there could be advantages.

“It is better for wealthy people to deal with someone who is an expert in their field rather than someone who jumps to the wrong conclusion as they don’t have the right experience,” he says.

The launch of the new high net worth teams comes as HMRC is generally taking a much tougher stance on tax avoidance.

This week it has also acquired enhanced powers to claw back unpaid tax. It now has greater rights to go into business premises to inspect tax records. If someone works from home, the Revenue can enter their property to examine records, often with little or no notice.

“The Revenue no longer has to wait until someone submits a tax return if it thinks there has been a transaction that could affect the tax due,” says Holmes.

The penalties for tax evasion are also rising. People committing the worst kind of evasion – where there has been serious and deliberate concealment – could now be fined up to 70 per cent of the tax due. Previously the fine was up to 40 per cent.