I don't buy precuts. I prewash all my fabrics and dry in the dryer. I use color catchers too.

I prewash everything except for jelly rolls. i don't want any surprises.

I wash and dry everything but pre-cuts which I rarely ever buy.

Same for me

Prewash? Yes. Let's me know if the fabric bleeds, shrinks it, and gets out any "extra" chemicals and dirt/dust. Basically I do a rinse and spin cycle. No soap usually. Reds, dark blues & purples, blacks...all subject to bleeding, so those go in a hot water bath by themselves. I like working with clean fabric, plus it helps keep my allergies at bay. The only fabric I don't prewash is by Quilting Treasures, because they put thier fabrics through a hot water wash after all the dyes are in it. So if I can find the Quilting Treasures, I buy that to save the prewash.

I just prewash flannel and use color catchers for the finished quilts. I don't have allergies and so far have not had any bleeders. I sometimes test a piece to see if it bleeds but haven't had any yet

I'm with dunster on this one. Some new fabric is so stiff from whatever they do to it, I really don't like working with it.

I pre-wash batiks and any fabric not purchased in store such as gifted or purchased at guild shows. I use lots of color catchers once quilt is completed...no problems so far...

As you can see, you've gotten a variety of answers, all valid. You have to decide what works for you. Initially (way, way back) I did not pre wash. Now I pre wash everything. I use color catchers, and I toss fabric in the dryer, then fold when it comes out. I don't iron, press or starch until I'm ready to use it. I do it because I am very sensitive to smells and chemicals, and found it almost impossible to work with unwashed fabric. You'll figure it out as you go!

I wash everything. Always.