I always pre-wash my fabric and Also, the binding. I purchased Wright triple fold binding for my quilt, in red, and just by accident I put the binding into water and the red ran. If I had used it as binding on my quilt, it would have ruined my quilt. That may have just been an accident, but, I don't take any chances. Also if I pre-shrink part of my fabric, in the quilt, I need to pre-shrink it all.