The Federal Reserve has released details of more than 21,000 transactions after being forced by the Dodd-Frank Wall Street Reform Act to disclose which institutions it had bailed out in the financial turmoil since December 2007.
The data reveals that British-based banks accounted for $1 trillion (£640bn) of the money the Fed issued to prop up the financial sector.
Barclays took the biggest chunk of bailout money, borrowing $863bn from the Fed. Almost half of the money came in overnight loans thought the Primary Dealer Credit Facility, a programme intended to help banks dealing in US Treasuries.
Barclays has since paid all of its loans, which came about because of Barclay's $1.75 purchase of Lehman Brothers.
Royal Bank of Scotland borrowed $446bn, Bank of Scotland $181bn, Abbey National $19bn and HSBC less than $10bn. The figures show each institution's total borrowing, not the amount they had outstanding at any one point.