About 58 percent of consumers polled say they likely would change banks if there was a $5 monthly fee increase, according to a report by the Deloitte Center for Financial Services. The finding suggests that banks could find it difficult to recoup fee revenue lost to new regulations. Consumers with checking accounts usually do not know how much their account may cost the bank. In the survey, 75 percent of customers say they believe it costs their bank less than $11 per month to service their checking accounts; in reality, the cost is closer to $20. The report, based on responses from more than 4,200 checking account customers, also found that 74 percent of customers are either satisfied or very satisfied with their primary bank. Interest margins have shrunk as new regulations make it tougher for banks to earn money from overdraft fees and debit card swipe fees, and fewer customers have free checking accounts. Only 39 percent of interest-free checking accounts are available for free, compared to 76 percent in 2009, according to Bankrate.com. Rather than raising prices broadly, the Deloitte report suggests that banks target specific offers at specific customers, based on demographic and certain psychological traits.