I don't, other than the usual places that aren't plus-sized precisely: local Salvation Army, Catholic Charities, Goodwill, etc.

In my town, a friend works at a kind of half-way house for homeless mothers, and she told me they're always looking for clothes and particularly plus sized, which don't seem to get donated as often. So maybe the same is true at other charities.

But maybe someone can help out with more like what you're looking for. Anyone?

I use to volunteer for my local Dress For Success and we were always in DESPERATE need of plus size clothing. While we preferred dress/business casual/interview attire type clothing, we would make an exception for plus size clothing and take everything. lol If we couldn't use it, we knew plenty of other charities that could because donations of clothing in our sizes was scarce.

Give them a call!

My community has a Facebook group specifically to buy and sell used plus size clothes. You could check and see if there's one like that in your area or even start one. Failing that, I've sold quite a few things that I was wearing at my largest size on Ebay.