How do I remove stains from white plastic( resin) chairs?

Hot soapy water and a scrub brush.....if that doesn't clean it well enough, use a Magic Eraser sponge on the tough spots.

Krud Kutter or TSP, trisodium phosphate. Problem with resin chairs dirt and grime gets embedded in them.

If you can't get the spots out, you could try painting the chairs. Krylon makes a good spray paint for plastic.

Try Dow Scrubbing Bubble, foam Maybe a few applications, but I clean my white cabinets, refrigerator and it works!

How do you remove dirt/dust from white plush chairs?

Bleach and dish soap and degreaser