Sometimes I prewash and other times I don't. Once a quilt is finished I wash it in Hot water and dry it in the dryer. That way if it's going to shrink it does it on my watch and not the receiver. If there are any problems they can be fixed at this time. Then when it is received, the receiver can do with it what they want and I don't have any worries of future problems with it. That's just me tho. I know it's not right, but it works for me.