I only have one card now. Over the past 20 yrs, I'd pick up an occasional line of credit for 0% offers, but closed them out when they were done. I don't plan to do that anymore because it's really just a hassle and I prefer to pay cash anyway. I have an air miles card, so when I do family travel this summer, I suspect I'll save upwards of $3k. They can be beneficial if used correctly, but unfortunately in the wrong hands, people can spiral downward real quick. I am thinking of opening a new BofA rewards card, just so I can separate my work card from my personal card. My company doesn't provide a card for us.