I was recently at a baby shower and the mom-to-be received close to 60 gifts. Saw so many beautiful ribbons and bows in pristine condition discarded. What charity might be able to use NON-Christmas ribbon if someone knows.
I believe almost any of your thrift stores would be happy to receive a bag of ribbons as these should be fast sellers.
Check Google for non-profit thrift stores with your zip.
I would suggest Habitat Resale Store, Humane Society, Hospice Stores as these are very good and do a lot of good for the community. I'm not a big fan of Goodwill.
Bag your ribbons in a large bag and let them rebag to their method.
There may be other charities but so many will no longer take 'used' items so be sure to check first (thrift stores will take them).
If you put it on Freecycle, it may not go to charity, but it will stay out of the landfill.
I have given Christmas and non- Christmas wrapping to the church thrift shop.
The charities in my town toss used bows/ribbons--meaning that they were already tied or had the sticky stuff removed, they go right to the trash--even if they are "pristine" any hint of pre-used, they are trash. I have seen them do that as people pull away from the donation site and I have seen bags of used ribbons and bows in their dumpsters. They just don't have room for things that don't bring in the big bucks.
You could try to put them on your local Facebook marketplaces (like a sale/want/trade group or flea market/garage sale group) or for a "curb alert" on NextDoor or a neighborhood site like that.
If you have "free stores" like we are blessed to have here in my town, they may take them. You would need to Google free store an your town to find if you have one. OR we also have free pantries--like the little libraries that pop up around the country--we have free little pantries where you can put food and other household items and people can take what they need.
Local libraries or senior centers or pre-schools may take them--be sure to ask first. I know one year when my nephews were in pre-school we donated a huge bag of stickers and used ribbons for a special project the kids were doing--but we asked first and were told there was a need.
If you do want to do a charity drop off, be sure to ask first.
Charities mainly accept financial donations, clothing, shoes and bags, kitchenware, books, toys and games, art and so on. Hardly any of them will deal with gift ribbons. It will be a terrible if the ribbons you have collected are thrown again into the trash.
It is better to find a way to somehow sell these gift ribbons at a low price, for example, to some very small shop.
Or make something of them for example, like here www.pinterest.com/
You can give to Goodwill, salvation army, or local thrift shops. You can also check with various shelters to donate.