The tax covers bonuses awarded between 9 December 2009 and 5 April next year.
Swiss newspaper NZZ am Sonntag also said UBS was considering a similar move and had in December mulled over moving posts out of London.
Both companies declined to comment on the matter when contacted by City A.M. yesterday.
“There is a constant assessment on where staff should be located,” a Credit Suisse spokesman said. “It is wrong to presume that there is a shift from London to Zurich,” he added.
Banking executives warned the Government that the one-off 50 per cent tax on bankers’ bonuses above £25,000 would lead to defections from the City.
Higher earners also pay 50 per cent rate of income tax, currently one of the highest in Europe.
Sean Drury, a partner at PricewaterhouseCoopers, said: “Countries like Switzerland will look increasingly attractive to to people.”