Washer hadn't paid extra for overdraft protection ("I find the concept of paying for a checking account irritating"), so she was hit with a slew of penalty fees. When the same thing happened a year later, she was hit again -- not just with $200 in fees, but with attitude.

She knew it was her fault, but the fees felt punitive because she'd been a customer for so long. "So I called customer service," she says, "and was handed off to a very strident manager who smugly reminded me that the same thing had happened before. That's when I told her I planned to move to a credit union."

Washer says she's found the credit-union policy regarding overdrafts much more accommodating.

"They charge a fee, but you have to be a repeat offender," she says. "And they let you know quickly if your account goes into the red. My bank would send a letter, which is a great way to guarantee you won't know for a couple of days. It's like they're hoping you don't notice too quickly so they can charge you every time something goes through."

Another plus: Washer's credit union doesn't charge a fee every time she uses an ATM.

"The bank ATM fees were annoying," she says. "I was usually being charged around $4 in fees to withdraw cash. At the credit union, they reimburse any ATM fees."

Lack of interest

"I try to pay off my credit cards every month, but in 2007, a payment arrived late," says Heather Murphy, a communications director from Chandler, Ariz.

As a result, Murphy's bank raised her interest rate from around 17% to an "obscene" 23%. Not surprisingly, Murphy contacted the bank to see whether there was a way around the higher rate, but the bank simply pointed to the terms and conditions regarding late payments.

And then it did something else. The bank told her she wasn't their kind of customer.

"The message I received from the bank was that they weren't interested in keeping my business because I didn't keep a rolling balance," she says. "I told them, 'Look at my history, look at all the years and years I've been with you,' and they said, 'Yeah, you typically pay off your balance every month.' I said, 'Yes, I do, isn't that awesome?' and they said, 'No, not really. We make money off of people who don't pay off their bill.'"

Miffed, Murphy talked to a credit union and was told that with her spotless credit history, she would be eligible for a 7.9%-interest-rate credit card.

"After learning that, I was kicking myself for even having a credit relationship with my bank," she says.

Interest was also behind the switch for Kelly Quintanilla, a marketing director from Grand Rapids, Mich., who had been with the same bank since she was 12.

"I stuck with them through high school, college and the early years of my career," she says, but when a local credit union advertised a 4%-interest checking account, she switched. "I thought I'd try it since I was earning pretty much no interest on my savings at the bank."

She got her car loan there for a low rate, too.

Big versus little

There are trade-offs, though, when it comes to switching from a big bank to a cozy credit union.

Michael Hanley, a certified public accountant with more than 300 small-business clients, says credit unions have offered his clients better loan rates and better business practices. (One customer was regularly paying about $1,500 a month in insufficient-fund and bounced-check fees, simply because his bank posted debits first and deposits last, even for deposits made first thing in the morning.)

But they can also mean more work on the bookkeeping end.

"Their bank statements tend to be fairly archaic," Hanley says. "And their online banking systems tend not to interface with QuickBooks as often as regular banks', so there can be a huge data-entry component."

Others point to a lack of locations as an issue.

"The lack of branches is the biggest problem for me," says Janice Sellers, an office manager from Oakland, Calif., who recently switched to a credit union after suffering a series of "rapacious" bank practices. Parking at her credit union is hard, and the hours don't mesh well with her work schedule.

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Still, the pluses seem to outweigh the minuses for many.

"It's smaller, it's more personable, and it's definitely easier to get questions answered," says Washer, who adds that switching to a credit union sooner could have saved her close to $500 in penalty fees. "Plus, for me, it's like the whole 'buy local' thing. Credit unions are doing well in terms of getting local customer loyalty. The financial crisis has just made people look at larger institutions with deserved skepticism."