The June FSA figures for PPI complaints show a drop for the first time this year.
Complaints have been steadily rising from £403.4m in January to £730.5m in May. But June saw a month-to-month fall to £614.8m.
The payment protection insurance (PPI) mis-selling scandal has cost financial services £3.3bn so far this year, according to the City watchdog's monthly PPI refund and compensation figures.