JPMorgan Chase is raising eyebrows by charging non–Chase customers $5 withdrawal fees at Chase ATMs in Illinois. But if this pilot program and another $4-a-pop one in Texas prove successful, getting cash may become more expensive nationwide. What's behind the sudden dramatic ratcheting up of ATM fees, and is there any way to avoid them? Here, a brief guide.

How is Chase justifying the fee hike?

ATMs are expensive to set up and maintain. Chase, for example, says it spends $200 million a year to run its 16,000 ATMs nationwide. Banks are also searching for new sources of revenue, thanks to the financial reform law that passed last year, which limits the amount they can charge customers for overdrafts or debit cards. "How depressing" that "regulations installed to help the man and woman on the street, are now working against them," says Katya Wachtel at Business Insider.

So it's Washington's fault?

Don't be so sure. ATM fees have been on the rise for decades, skeptics note, and the timing here is suspicious. Banks are lobbying Congress heavily to postpone the April 21 start of the debit-card restrictions, and this stinks of "a scare tactic aimed at roiling congressional waters," says Ed Mierzwinski at the U.S. Public Interest Research Group.

How high might ATM fees go?

It depends. There are two sorts of fees: The charges a bank may levy on non-customers to use one of its ATMs (an average of $2.60), and what banks charge their own customers to use their cards at competing ATMs (an average of $3). "The risk, of course, is that banking customers will feel nickel-and-dimed to death" and seek out another bank, says Shira Ovide at The Wall Street Journal.

Are we doomed, then, to higher service charges?

Probably, says CardHub.com CEO Odysseas Papadimitriou. To compete for customers, "banks are going to try to minimize the monthly fees and load you with fees in different ways — and ATM fees are going to become one of the most popular ways to do that." But there's a simple (if not always convenient) way to avoid the fees, consumer advocates say: Only use ATMs run by your own bank.

Sources: CNNMoney.com, Business Insider, Wall St. Journal, Credit.com