Federal regulators have lowered the estimated cost of bank failures by $8 billion over four years and are proposing no increase in the fees banks pay to replenish the fund that insures deposits.

The Federal Deposit Insurance Corp. provided the new estimate Tuesday of $52 billion in losses from 2010 to 2014, down from a previous projection of $60 billion. The FDIC said that losses to the insurance fund from failures this year, around $20 billion, have been less than expected.

The financial overhaul law enacted last summer mandates that the insurance fund be restored to at least 1.35 percent of total insured bank deposits by 2020. With 297 banks having failed since the start of 2008, the fund was in the red by $20.7 billion as of June 30 and was at 0.28 percent of total deposits.