How to Seal Quartz Countertops (And When You Actually Need To)

Here's how to evaluate your countertop and decide what kind of protection it actually needs.

1. Clean and dry the surface completely. Wipe down the entire countertop with a mild, pH-neutral cleaner and let it dry fully. Any residue, grease, or moisture will mask existing damage and interfere with anything you apply afterward.
2. Test for existing damage and etch marks. Once dry, inspect the surface under raking light, a flashlight held at a low angle works well, for dull spots, faint rings, or hazing near the sink and stove. These are early signs of acid or heat exposure. Run a hand across the surface too. A loss of sheen you can feel usually means the resin has already been affected.
3. Decide between a topical protectant and a permanent nanocoating. A topical polish or protectant sits on the surface and can restore shine and add mild resistance, but it wears off with normal use and needs to be reapplied regularly, often every few months. A permanent nanocoating like RAKU works differently: it bonds at the molecular level rather than sitting on top, so it doesn't wear off, yellow, crack, or peel. RAKU is applied in a single day with no operational downtime for your kitchen, carries a 10-year commercial warranty, resists heat up to 1,900°F, and is food-safe once cured. For a quartz countertop that sees heavy daily use, that's a meaningfully different level of protection than a bottle of polish from the hardware store.
4. Know that RAKU is not a DIY product. It's applied exclusively by certified applicators trained in the process. This isn't a sealer you brush on yourself. It's a professional treatment, which is also why it can deliver permanent, warrantied results that consumer products can't match.

Why Quartz and Marble Aren't the Same Conversation

Marble is a natural stone with high porosity. Its surface is full of microscopic channels that absorb liquid, oil, and acid on contact, which is why traditional sealing, and eventually a permanent coating, is essential to prevent staining and etching. Quartz is engineered specifically to minimize that porosity, combining crushed stone with resin under pressure to create a much tighter, less absorbent surface. That's why quartz rarely stains from everyday spills the way unsealed marble does. But low porosity doesn't mean invulnerable. Quartz's resin content is exactly what makes it vulnerable to heat and certain chemicals, a different failure mode than marble's absorbency. The protection strategy has to match the material, not just the marketing term "sealing."

If you want a coating built for quartz's specific vulnerabilities rather than a generic sealer, see our full quartz protection service. And if you're dealing with natural stone like marble, onyx, or travertine, where porosity actually is the core issue, read our marble sealing guide for the full breakdown.