In the six weeks or so since I started keeping and counting the offers I received rather than trashing them, I’ve collected eight, some offering cash back or other rewards, but all of them using zero percent as bait for signing up.

The catch—and there usually is one, despite consumer-friendly improvements brought about by credit card reform legislation enacted last year—is that you’re likely to pay higher fees for transferring balances to these cards with zero percent rates. A recent study conducted by the Pew Health Group analyzed 450 online card offers and found that the average balance transfer fee charged by the nation’s largest banks rose from 3 percent of the amount transferred in July 2009 to 4 percent in March 2010.

So before you take the zero percent bait, do the math to see what it’s going to cost you in fees if you’re transferring a balance.  You also may save money by going with a teaser rate on a card offered by a credit union.  As we’ve reported in Consumer Reports Money Adviser, qualifying to obtain such cards is easier than it used to be. The Pew study found that the average balance transfer fee on credit union cards was only 2.50 percent, the same as it was back in July 2009. And while the median period for which teaser rates applied on bank cards was seven months, the study found it was 24 months for credit union cards.—Andrea Rock