I started out buying 1 yard, but now find that I usually need more to make a quilt. So I have been buying 2 1/2 yds, but I really should buy 3 yards like most here suggest. That is usually what I have needed and not had. I like to make mystery quilts, so 3 yards should be enough for most of them. I tend not to buy plains because I can always find what I need at a LQS that will work.