Swiss banks could end up paying as much as US$520 million as their British clients, spurn a deal that would preserve their anonymity and reach individual settlements with UK tax authorities.

The Swiss Bankers Association (SBA) said last Friday that many of their UK clients chose to come clean with tax authorities. The move was to pay the due taxes on their accounts instead of making a one-off punitive tax payment that would allow them to stay anonymous.

Last January 1, Swiss banks paid 500 million francs to Britain over a signed deal. The said deal stipulated that they will only receive the full amount of money they have paid for after their UK resident clients pay at least 1.3 billion francs through the anonymity scheme. The scheme would allow said clients to stay anonymous rather than direct to Britain.

On Friday, Credit Suisse said that it would book a maximum charge of 90 million francs in the second quarter. The increase was due to the level of client payments. Its bigger rival, UBS stated that it would report the impact in its second quarter results.