Swiss authorities say they have handed over details of more than 2,000 wealthy American clients of Swiss bank UBS suspected of tax evasion.
Files on a total of 4,450 accounts will be given to Washington by the autumn.
US tax officials said they now expect civil legal action against UBS to be withdrawn.
The agreement to hand over the information shattered Switzerland’s cherished tradition of banking secrecy.
Switzerland’s banks should not run into further trouble with the US tax authorities now the damaging dispute with UBS had been cleared up, Switzerland’s top tax diplomat, Michael Ambuehl, said earlier this month.