Yes—absolutely, an outdoor bench color change is doable. You can paint over an outdoor bench later if you change your mind about the color, and repainting an outdoor bench is often easier than replacing it. I’ve done this on a wooden bench that went from dark brown to sage green and then to navy, and it held up beautifully.
The key is preparation. If the existing finish is in good shape, clean the bench thoroughly with mild soap or a degreaser, rinse it well, and let it dry completely. Lightly sand the surface with 120- to 220-grit sandpaper to scuff it up so the new paint can grip. Wipe away the dust with a tack cloth. If there is peeling paint, flaking finish, or rust, remove that first—use a scraper and sandpaper for wood, or a wire brush for metal. For any bare spots, apply an exterior primer, especially on wood or metal.
Choose the right exterior bench paint for the material. For wood, use an exterior latex or alkyd enamel. For metal, choose a rust-inhibiting exterior paint. For plastic, a spray paint made specifically for plastic usually bonds best. Apply thin coats rather than one thick coat. Two or three light coats will give you a smoother, longer-lasting finish. Let each coat dry according to the label, and give the final finish at least 24 to 48 hours to cure before heavy use.
If the old surface is very glossy, sanding becomes even more important. If the current paint is oil-based and you want to switch to water-based, use a bonding primer first. If the bench is stained rather than painted, you can still paint over it—just sand lightly and apply a stain-blocking exterior primer.
For painting outdoor furniture, prep is always the difference between a finish that lasts and one that peels. So yes, changing the color later is completely possible. With proper prep and the right paint, your bench can look brand new and hold up outdoors for years.