There is a startup in Germany that recycles filament: https://recyclingfabrik.com/

They even provide shipping labels from Germany and Europe if you send in a certain amount. You can also buy their recycled products.

I don't think there are any USA-based companies or programs that are truly worth it. I feel like the extra carbon burned to ship the scraps to the ones that do exist does more harm to the planet than whatever we may gain from recycling the plastic.

And also the companies that sell recycled spools of plastic aren't selling them for less than the price of virgin material, and those rolls will be a mishmash of plastics that aren't the same quality. I can't imagine that they will print well enough to do much other than prototype something with them.

It's a shame, and I wish things were different. Your best bet is to recycle it at home, but that's not cheap. Stefan at CNC Kitchen talks about and demonstrates this in his videos: https://www.cnckitchen.com/blog/recycling-old-3d-prints-into-new-filament

To be honest: not really. The plastic can be recycled well enough, but there's no good way to turn it back into a filament. There's a few products out there that purport to, but none do a great job so far.

Find some molds and melt it down and use for Halloween decorations. Mini skulls and bones work pretty well.

Ive seen many questions like this and Im always intersted in new ideas. So far didnt find anything that would suit me. I know some people melt it into big blocks or plates (dont use your kitchen oven 🤣) for future projects. Making filament from that is probably not worth. I successfully recicled maybe 1% by filling hollow prints with that trash to gain some weight 😉

Following to see other comments

There's at least one Canadian manufacturer with a recycling program, although they don't offer you any credit for sending them scrap ( https://filaments.ca/pages/recycling ), and I expect there are some in the US. The "melt into slabs in a secondhand toaster oven and use to make a small shelving unit" approach is probably cheaper over time, though (alternatively, melt it in a soft drink can and make plastic mallet heads).

Add:north has a recycling program for PLA, but there's a minimum of 5kg material + 5 filament spools. They also only accept their own PLA and there's a large warning on the site that you can sabotage the recycling process if you mix in material from other manufacturers, since they will likely have different additives.

There's also some more generic info which implies that you shouldn't put PLA in the general plastics recycling (at least not in Sweden) since they can't take care of it, and that PLA can contaminate other polymers that the recycling plant could otherwise handle.

There is no way for 99% of us to recycle any of our pla or petg. There are a few pilot programs one in Germany. They have you ship them your scrap and give you credit towards a recycled spool.