Yes—there are special anti-graffiti coatings made for outdoor benches, and they work much better than regular paint or clear sealers. The two main types are sacrificial coatings and permanent or semi-permanent coatings.
Sacrificial coatings are usually wax, acrylic, or siloxane-based. They form a thin clear barrier over the bench. When someone tags the bench, you remove the graffiti with hot water or low-pressure washing, and the coating comes off with the paint. After that, you simply reapply the coating. These are cheaper and easier to apply, but they need recoating after each cleanup.
Permanent and semi-permanent coatings are tougher: polyurethane, epoxy, fluoropolymer, or nano-ceramic formulas. They create a hard, non-porous, slick surface that spray paint cannot grip strongly. Graffiti can usually be removed with a mild solvent or dedicated graffiti remover without damaging the bench underneath. These coatings cost more and require proper surface preparation, but they can last for years.
For most outdoor benches, I would recommend a two-part polyurethane or a siloxane-based anti-graffiti system if the bench is metal or powder-coated. For bare wood, use a penetrating anti-graffiti sealer first, then apply a clear topical coating. Always test on a hidden spot, apply in dry weather, and follow the recoat window.
Coatings help a lot, but they are not magic. Combine them with good placement: keep benches in visible, well-lit areas. Use darker colors, textured surfaces, or busy patterns that make tags less attractive. Remove any graffiti within 24–48 hours because taggers are less likely to return to clean surfaces. If you want the lowest-maintenance option, choose a permanent anti-graffiti coating and keep a small graffiti removal kit nearby.