I have washed W&N, loosely following directions on the package. I say loosely because I did wash in the washing machine, I did let it agitate very briefly on gentle cycle, and I let it spin dry before putting it in the dryer. I did it because for one particular quilt I did not want any shrinkage of the batt after I did the quilting. (And at this point I can't even remember which quilt I did this for!)