As retail banks both large and small face various tribulations, credit unions are benefiting. In a release today, the Washington Credit Union League reports that in the third quarter “173,464 consumers joined one of the state’s 119 financial cooperatives.”

That tally, the league said, “shatters all previous quarterly membership increases and brings Washington state’s total credit union membership to 2,795,489, or 42 percent of the state’s estimated population of 6,668,200.”

“Media reports on problematic banks seemingly have made Washingtonians suspicious of profit driven financial institutions, especially big Wall Street banks,” said Washington Credit Union League President & CEO John Annaloro. “Ten percent yearly growth was unheard of prior to this extraordinary migration to credit unions.”

A spokesman for the state bankers association was unavailable for comment this morning.

The credit union league continues, “This year’s third quarter membership summary brings 2009’s total new membership to 240,485, slightly less than the combined populations of Tacoma and Olympia.”

The report goes on to speculate that the media may bear some responsibility for the increase in credit union membership, having reported, for example, the results of a Pew Charitable Trust study that found credit cards offered by credit unions can generally provide better terms than those provided by cards issued by large banks.