When officials with the parent company of First Tennessee Bank walked through the company’s second quarter earnings in July for analysts, they noted that the implementation of stricter rules governing debit card fees would mean an annual $15 million to $20 million hit to the company’s revenue.

Starting Oct. 1, banks like First Tennessee will have a cap on the fees they’re allowed to collect from merchants whenever customers swipe their debit cards to make a purchase. But during its earnings presentation, William “BJ” Losch – chief financial officer of First Tennessee’s Memphis-based parent First Horizon National Corp. – said the impact of the company’s expected hit could be mitigated.

He mentioned possibilities like hiking existing product fees and reducing fee waivers.

Starting later this month, First Tennessee will take a big step in that direction. It’s rolling out its own version of a change that other banks are making in response to the government setting a cap on certain fees, such as the fees that banks collect from merchants.

First Tennessee soon will join other banks in charging customers each month to use their debit cards. Such moves have recently prompted a customer backlash elsewhere at places like Bank of America Corp., the largest U.S. bank by assets that’s decided to start charging customers a $5 monthly fee for debit card usage.

Bank of America is launching the fee starting in 2012.

Other banks – like SunTrust Banks Inc. and Regions Financial Corp. – also have either started or are moving toward flat per-month fees for debit card users. And some of those customers have flocked in droves to social media outlets in recent days to voice their dismay at what they see as being asked to pay extra money to spend their own money.

SunTrust has been charging a $5 debit card fee for customers with basic checking accounts since the summer, and Regions this month begins charging a $4 fee.

Meanwhile, First Tennessee decided on a per-use fee, instead of a flat monthly fee, for its change that begins Oct. 22. The fee will be 4 cents for PIN transactions and 14 cents on signature transactions, up to a maximum monthly amount of $3.

“Some banks are charging a flat rate for debit cards, but we wanted to be as customer friendly as possible and only charge for use,” said Dave Miller, head of consumer banking at First Tennessee.

First Tennessee also is touting the fact that there’s no charge for customers to withdraw cash from a First Tennessee ATM, and the fees don’t apply to certain checking accounts.

“Plus, First Tennessee still offers a cash rewards feature on our debit card, which many banks no longer do,” Miller said. “So we tried to minimize the impact on the customer and maximize the value.”

Offering cash rewards on purchases is becoming less frequent at a time when the banking industry is cutting back on rewards and hiking fees in response to new regulations.

The debit card fee implementation also is a sign of a sea change in the bank industry, the customers of which had become accustomed through the years to free perks like Internet banking, debit card usage, and no minimum balance requirement on basic checking accounts, most of which had become standard features of the banking experience.