(Bloomberg) -- Overdraft fees rose to a record this year, even as many of the biggest U.S. banks take steps to wean themselves off the increasingly contentious revenue source. 

The average cost to overdraw a checking account climbed to $33.58 from $33.47 last year, according to a Bankrate study released Wednesday. The figure increased for a third straight year, with Philadelphia having the highest average fee among major metropolitan areas, at $35.70, and Cincinnati at the bottom, at $30.42.

Bankrate Chief Financial Analyst Greg McBride said consumers can take steps to avoid incurring the charges. “Set up a link between your checking account and savings account so you automatically cover any shortfall and avoid overdrafts,” McBride said in a statement. “Be proactive to avoid overdrafts as inadvertent slip-ups do occur.”

Frequent users of overdraft protection -- consumers who use the service one or more times in a month -- account for more than half the profitability of mass-market checking accounts, according to a 2020 report by the consultancy Oliver Wyman Inc. That means lower-income consumers often subsidize the free checking accounts used by their wealthier counterparts.

That’s sparked the ire of consumers, regulators and lawmakers. At a Senate Banking Committee hearing in May, Massachusetts Democrat Elizabeth Warren lit into top executives in the banking industry, calling JPMorgan Chase & Co.’s Jamie Dimon the “star of the overdraft show.” Dimon said her figures were “totally inaccurate.” 

Bank of America Corp. said in September it was taking additional steps to help customers avoid the fees, rolling out a new service that automatically moves money from other accounts into checking accounts when needed for a $12 fee. 

According to the Bankrate study of the industry, 48% of non-interest accounts are free, but just 8% of interest-earning accounts are free. The required balance to waive a monthly fee for an interest-bearing checking account soared 31% to a record $ 9,897 from last year’s $7,550, while the amount for non-interest accounts sank to a 10-year low of about $507. 

Fees for using out-of-network automated teller machines dropped, with the average total cost of such transactions falling to $4.59 from the record $4.72 set in 2019. People withdrawing money from ATMs in Atlanta pay the highest fee, of $5.23, while those in Los Angeles are charged $3.90, the lowest of the metropolitan areas surveyed.

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