HMRC has warned that time is running out for expats and taxpayers with offshore accounts and investments who have not declared their interests to the tax man.
Financial advisers who have referred a client to an overseas financial institution or pointed them towards offshore advice or services must declare the information to HM Revenue & Customs by the end of this month.
At the same time, an adviser who has suggested clients take offshore advice or services since April 5, 2015 must warn them that HMRC has new powers to discover information about offshore cash and investments, Money International reports.
There is an incorrect assumption that people cease to be tax resident in the UK when they work abroad but very often a UK tax liability will arise on foreign earnings"
The warning must be made using a template drafted by HMRC explaining how the tax authority now shares financial information with more than 100 countries - including British Crown Dependencies and Overseas Territories.
Expats who have British tax liabilities are contributing an increasing amount to the Exchequer as the tax take has increased eightfold in just five years.
Last year HM Revenue & Customs collected £6.5m via requests made to foreign tax authorities, an increase from the £796,835 collected in 2013.
Disclosing this 716% leap over the five-year period, Access Financial said it was triggered by 709 data requests by HMRC to non-UK tax offices. But not all the resulting £6.5m was due to deliberate avoiders.
"There is an incorrect assumption that people cease to be tax resident in the UK when they work abroad but very often a UK tax liability will arise on foreign earnings," the firm said.
"A significant proportion of British contractors who are working abroad, or have worked abroad recently, are likely to have not paid the correct amount of tax. The likelihood of HMRC catching up with them is much greater now than at any time in the past."