Those with money hidden away in offshore accounts now have until June 22nd to announce their intentions to declare their assets, Revenue and Customs (HMRC) has announced.
Under the amnesty those in question will have to make all payments of tax, duties and interest by November 26th and will be fined ten per cent of the underpaid tax.
This represents a large reduction of the normal fine, which can be as much as 100 per cent of the underpaid tax.
And for the disclosure of amounts up to £2,500 there will be no penalty at all.
The amnesty, which covers VAT, capital gains tax, national insurance contributions, corporation tax and inheritance tax, is expected to reap billions of pounds for the government.
Last year HMRC successfully forced several high street banks to divulge the details of clients who had overseas accounts.
Ernst & Young comments on HMRC amnesty
Chris Oates, leader of Tax Risk Management at Ernst & Young, said: "This move emphasises HRMC's increasingly active approach in tackling the use of offshore bank accounts for tax evasion purposes.
"How much of an incentive the ten per cent penalty ceiling is remains to be seen."
There is no immunity from being prosecuted, which means that any disclosure could be used to prosecute a taxpayer, added Mr Oates.
It is because the HMRC is already holding extensive information on those with offshore accounts that these taxpayers would want to take advantage of the amnesty while they can, he continued.
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