The original DFS fine will cut pretax profit growth this year to around 5%, from an underlying profit rise of more than 10%, the bank said in a trading update- so the additional payment could leave profits near flat on the year.
The DFS, New York's banking regulator, said Standard Chartered had hidden financial transactions with Iran.
The bank agreed to pay the civil penalty after its stock dropped due to the allegations and a threat to revoke its license to do business in New York.
The United States has led the drive for sanctions, hoping to halt an Iranian nuclear program which Washington suspects is aimed at producing weapons although Tehran says it is peaceful.
Even slim earnings growth would mean a 10th straight year of record profits, as StanChart has ridden on Asia's rise through much of the last decade, allowing it to continue hiring and increasing earnings when much of the industry is shrinking.
Finance director Richard Meddings estimated Standard Chartered could have to pay $320-330 million next year under a British bank levy.