Barclays bank has paid a further $100m (£77m) to settle a claim by 44 US states that it rigged the Libor rate system between 2005 and 2009.
Libor – or London inter-bank offered rate – is used by banks to set the cost of lending money to each other.
The New York attorney-general, Eric Schneiderman said government bodies and not-for-profit organisations had been defrauded of millions of dollars.
The Libor scandal has already cost Barclays $453m.
That sum was paid to the US Justice Department, the US Commodity Futures Trading Commission and the UK’s Financial Services Authority in 2012.
As part of the latest legal settlement, Barclays admitted what had already been firmly established; that some of its dealers rigged Libor rates in a system of mutual back-scratching between 2005 and 2009.
Mr Schneiderman said: “There has to be one set of rules for everyone, no matter how rich or how powerful, and that includes big banks and other financial institutions that engage in fraud or impair the fair functioning of financial markets.”
Other banks that have reached settlements with the US authorities in similar Libor cases include UBS, which paid $1.5bn (£940m), RBS, Deutsche Bank and ICAP.
But Mr Schneiderman said Barclays was the first bank to settle cases brought by individual US state authorities.
For its part, Barclays said it was “pleased” to have settled this latest legal threat in the US.
“We believe this settlement is in the best interests of our shareholders and clients,” it said.