In 2014, credit union membership grew 3.6 percent, the most in 20 years, according to Credit Union National Association estimates. Loans from credit unions increased 10.2 percent, the most since 2005, driven in part by an improving economy. "The credit union movement appears to be gaining momentum with consumers," said Greg McBride, chief financial analyst at Bankrate.com.

They are poorly named

Contrary to some perceptions of the name, credit unions have nothing to do with credit reports and scores and are not affiliated with a labor union. "We've historically struggled with the nomenclature," said Mike Schenk, vice president of economics and statistics at Credit Union National Association.

Joining is easier than you think

One drawback of credit unions is you have to qualify to join. But it's far simpler to qualify than a generation ago, and you probably could qualify for more than one, maybe based only on where you live. However, if you have a lot of money to deposit and use a wide variety of services, especially business services, you might find lucrative offerings and great service at traditional banks, McBride said.

Fees are more palatable

Fees are fewer and lower at credit unions. Bankrate has found that 72 percent of the nation's biggest credit unions offer free checking accounts, compared with 38 percent of the nation's largest banks. The average overdraft fee at credit unions is $26.78, compared with $32.74 at banks.

Loan rates are probably lower

Financing a $25,000 new car for five years would cost $800 less in interest with a credit union loan compared with a bank loan, on average, according to the Credit Union National Association. Home equity loans and mortgage rates are only somewhat lower, however.

Credit card rates are more favorable

If you carry a balance on a credit card, which for the record is a bad idea, credit union finance charges are lower. For a rewards card, the average interest rate is 9.9 percent, compared with 12.2 percent for banks. A regular credit card is about 1 percentage point lower, on average.

CHICAGO TRIBUNE