I do the same as Misty's Mom for big quilts....I use 2.5 inch on small quilts, 3 inch on medium quilts and 3.5 inch on really large quilts. I do this because I think the wider bindings look better on larger quilts for a more balance look. I use 3/8 seam (the width of my walking foot with needed moved) for the 2.5 and 3 inch binding) and generous 1/2 seam on the 3.5 binding. I think they look great.