US expatriates and many foreigners living in the US risk penalties of up to $10,000 if they fail to report details of overseas bank and financial accounts to the US Treasury by Thursday.

Any “US person” who held more than $10,000 (€8,269, £5,532) offshore in 2004 whether in bank accounts, stock funds, trusts and other investment accounts is expected to have completed an obscure form known as a TDF 90-22.1.