I do prewash (and recommend) prewashing cotton fabric in hotter water than I would use to wash a quilt. I do wash like colors together. I throw in a color catcher. I want whatever is going to happen to happen before it gets sewn into a quilt. I also dry on med hot. It is 100% cotton - it should be able to withstand hot water. I use regular detergent. The recipient is going to use regular detergent. I do not use dryer sheets or fabric softener - don't use them on my clothing - I am washing the fabric to remove the sizing and whatever is on it, No need to add it back in.
On long pieces, I baste the short ends (WOF) to avoid the twisting mess. If it is 2 yards or longer, I will randomly baste the long edges (selvages) a few stitches every foot.

I also prewash Fat Quarters and short pieces in a bowl in the sink - hot water. Blot excess on a white towel. Again, I want the dye or fading to occur before it is used.

I am diligent about prewashing. Always have been since I was a young girl sewing - before dryers.

I am not a fan of Woolite.

Many do not prewash.

Yes, I wash my finished quilts. I wash them on warm, gentle, use Dreft, dry on medium - remove from dryer when slightly damp - block if necessary - laying on the floor on a sheet to finish drying.

I don't usually prewash. I have recieved so many blocks from quilters, and have never known what was pre-washed or not, that I just gave it up.

I always wash my finished quilts in warm with a few color-catchers in the wash. I dry on medium to high. I like the differential shrinkage and the "puff" that happens when a quilt is washed.

I don't expect my quilts to be babied by the recipient, and I certainly don't want to do it to the ones I keep.

You will get so many answers to this question - but in the end, you need to do what works for you.

That's a good question and sure to bring out a variety of opinions.

I almost never pre-wash and now that I've gotten into jelly rolls and charm packs I wouldn't even consider it. Like Mary C, I wash once the quilt is done and use a color catcher in the wash. I know partly it's luck, but I've never had a problem. My own quilts are washed, often in hot water because of the dogs and cats, and machine dried. It works for me.

Kate

Please take note that the fabric that shrunk so badly was unbleached muslin. I've never had a problem before because I've always pre-washed all fabric as soon as it came in the door. But on this particular occasion, since the bolt actually had "preshrunk" on it, I took a chance with it. This was a whole bolt of muslin that I bought because it was on sale. So since I always pre-wash I have no idea if the regular quilting cotton at Joann's will shrink or not, but I just don't take the chance. I also wash all quilts after they are complete, regular soap, warm water, regular dryer cycle. I've never had a problem with them.

I like Bali Pops, and cannot prewash them. If I have to pair them with a contrasting fabric, I am afraid to use white or cream, because of the dyes---just haven't gotten brave enough the color catchers will catch all the fugitive dyes!
I think my HE front load washer makes the issue much-much worse because of the lack of water and the way the fabric, quilt is always laying on itself. Water supply is also a factor.
We have so many decisions to make! We are so lucky to be able to share our experiences here with such knowledgeable people!

Ritaweed...yes, yours is the story I recall that got me started on washing my stash! Everything is so clean now. Thks for the story... Sorry for your result. Btw I purchased that same muslim , but hadn't used it yet.

MRG: you are more diligent than I will ever be or could be... Way to go
Kate: I'm with you on the charm packs/ jelly rolls - I don't want to even think of a prewash!
Thanks all... I've never used the color catcher, sounds like I need to invest.
V.