The bank had appealed against the bail after it was charged with tax fraud in July but the appeals court ruled the amount should stand and the bank is supposed to pay by September 30th.
UBS's Swiss business is suspected of illegally canvassing French customers and setting up dual accounts to hide the movement of capital into Switzerland.
"UBS is very disappointed at the decision which fails to take into account the arguments put forward at the hearing," the bank said in a statement, adding it would launch an appeal.
The charges relate to money kept in accounts in Switzerland between 2004 and 2012.
A probe was launched after former UBS employees blew the whistle.
UBS denies the charges.
"We continue to believe that this is a highly politicized process that from the beginning of the investigation has not followed elementary facets of the rule of law," the bank said.