How to Seal Marble and Natural Stone Tile

What a sealer does, and what it doesn't

The Natural Stone Institute points out that most stone "sealers" are really impregnators: they sit inside the stone and act as a repellent rather than forming a seal. The result is more time to wipe up a spill before it soaks in.

A sealer doesn't make stone stain proof, waterproof or maintenance-free. It also doesn't protect against etching. Etching is a dull mark left when an acid, such as citrus, vinegar or wine, reacts with the calcium carbonate in stones like marble and travertine. See Etching vs Staining on Marble.

Marble seal or marble sealer? What the words mean

People search for a marble seal, a marble sealer, a marble tile sealer or a natural stone sealant. They all mean the same thing: a liquid you apply so the stone absorbs less. Stone-care pros call the usual type an impregnating (or penetrating) sealer. It soaks in and stays inside the stone, so you can't see or feel it once it dries.

No marble sealer is permanent, and none makes stone stain proof. Think of it as a repellent that buys you time. Pair it with the everyday habits in our Natural Stone Care & Maintenance Guide, and read What Is Marble? if you want to know why marble is so sensitive to acids.

Does your stone need sealing? The water-drop test

Place a few drops of water on the stone and leave them for about 15 minutes. Then wipe the area dry.

• The stone darkened: water soaked in, and a sealer can help.
• Nothing changed: the stone isn't absorbing much. It may not need a sealer, or an earlier sealer is still working.

Not every stone needs sealing. Repeat the test before resealing rather than resealing on a calendar.

The three kinds of sealer

For most marble and travertine tile, an impregnating sealer is the usual choice. On kitchen floors and near oils, choose an oil- and water-repellent (oleophobic) version.

Marble tile sealer: how to choose one

Choosing a marble tile sealer is mostly about reading the label. Look for five things:

• It says it is for marble, or for calcareous (calcite-based) stone.
• It is an impregnating (penetrating) type, unless you want a surface film on purpose.
• It suits the spot: floor, shower, kitchen backsplash, indoors or out.
• It is oil- and water-repellent (oleophobic) if the tile sits near cooking.
• It has clear instructions, including how to test it and when to wipe off the excess.

We don't recommend sealer brands. Formulas change, so the label on the bottle in your hand is your best guide. Whatever you pick, test it on a spare tile first. Samples help too: any 5 samples are $25 and ship free, so you can try the water-drop test on real stone before you buy. Planning the whole job? Our buying guide and installation guide cover what comes before and after the tile arrives.

How to seal marble tile, step by step

These steps are general. The sealer maker's label always comes first.

1. Confirm the sealer is labeled for marble or calcareous stone, and for the location (interior, exterior, shower or floor).
2. Let a new installation cure for the time the grout and setting materials require.
3. Clean the surface with a pH-neutral stone cleaner and let it dry completely.
4. Test the sealer on a spare tile or a hidden corner. Check that it doesn't change the color or sheen in a way you don't want.
5. Apply it evenly, following the label for coverage, ventilation and dwell time.
6. Wipe off the excess before it dries on the surface. Leftover sealer can leave haze or streaks.
7. Let it cure for the time the label gives before walking on it or getting it wet.
8. Repeat the water-drop test afterward to check the result.

How often to reseal

There's no universal schedule. Stone restorers quoted by the Natural Stone Institute's Use Natural Stone site disagree: one suggests every nine months to a year, while another suggests five to ten years. The same article notes some sealers last more than ten years and others only six months. Follow the product label, and reseal when the water-drop test shows the stone absorbing again.

Good to know

• More sealer isn't better. Excess sealer leaves haze and can't sink in.
• Sealed marble still etches. Wipe up acidic spills quickly.
• Keep a few spare tiles from your order. They're useful for testing sealers and cleaners.

Marble sealer questions: do you need one, and which kind?

Does marble need to be sealed?

Not always, but most people choose to. Polished marble absorbs less than honed, yet both can stain. A sealer gives you more time to wipe up a spill. Try the water-drop test above: if the stone darkens, sealing can help. Kitchens and bathrooms are where people seal most often.

What happens if marble is left unsealed?

Nothing dramatic. Unsealed marble isn't ruined, it just absorbs liquids faster, so oil, wine and coffee can leave a stain if they sit. It etches the same way sealed or not, because sealer doesn't stop acid. If you skip sealing, blot spills quickly and keep a few spare tiles. See how to remove stains from marble.

What is the best marble sealer?

The best marble sealer is one made for marble, suited to the spot and used exactly as its label says. For most tile that means an impregnating (penetrating) sealer, and near cooking an oil- and water-repellent one. A high quality sealer also has clear instructions and tells you how long it lasts. We don't name brands, so use the checklist in Marble tile sealer: how to choose one and test on a spare tile.

What is a penetrating or impregnating marble sealer?

It's a liquid that soaks into the stone and sits inside the pores, repelling water (and sometimes oil) from within. Once dry you usually can't see it, and it lets water vapor escape. It's the usual choice for marble tile. The table in The three kinds of sealer compares it with the other types.

Can I use a water-based or non-toxic marble sealer?

Water-based and low-odor impregnating sealers for marble exist. Whatever the type, check the label for what it's made for, how much ventilation it needs and its cure time. If you want a non-toxic product, read the maker's safety information and ask whether it's suitable near food. We can't vouch for third-party products.

Is there a high-gloss marble sealer?

A sealer isn't what makes marble shiny. Polished marble gets its gloss from the factory polish, and an impregnating sealer leaves the look as it is. Film-forming (topical) coatings add sheen, but they trap water vapor and wear unevenly, so stone pros usually steer away from them on marble tile. If you want shine, choose a polished finish. See honed vs polished stone or browse polished marble tile. On polished marble, wipe off every trace of excess sealer so it doesn't leave haze.

Should I use a marble cleaner and sealer in one product?

Cleaning and sealing are two steps. Clean first with a pH-neutral stone cleaner, let the stone dry, then seal. If a product claims to do both, check that the label says it's for marble and test it on a spare tile. Follow the maker's cure time either way.

How often should I seal marble, and is any sealer permanent?

No sealer is permanent. How often to seal marble depends on the product, the spot and the traffic, so there's no set date. Repeat the water-drop test and reseal when the stone starts absorbing again. The details are in How often to reseal.

How to seal a marble floor, honed marble and Carrara

How do I seal a marble floor?

Let the floor cure, then clean it with a pH-neutral stone cleaner (see how to clean marble floors) and let it dry completely. Test the sealer on a spare tile. Then apply it evenly in thin coats, wipe off the excess and let it cure before foot traffic, all following the label. Check the water-drop test in busy spots, like doorways, before you reseal. The same steps work for sealing a stone floor in travertine, limestone or other marble tile. Browse marble floor tile to see what's in stock.

How do I seal honed marble?

Honed marble is matte and a little more absorbent, so a sealer is often worth it. Some sealers darken honed stone, and color-enhancing ones deepen it a lot, so test a spare tile and let it dry fully before you decide. Choose a sealer labeled for honed or textured marble. See honed marble tile and honed vs polished stone.

How do I seal Carrara marble?

Carrara is light, and light stone shows stains. Seal it the same way as other marble: impregnating sealer made for marble, a spare-tile test, thin even coats, and wiping off the excess. Sealing helps with spills but won't stop etching. Learn more on our Carrara marble guide or browse Bianco Carrara tile.

Sealing marble in showers, backsplashes and walls

How do I seal marble bathroom and shower tile?

To seal bathroom tile made of marble, use a sealer labeled for marble and for wet areas. Let the stone and grout dry fully first, and ventilate while it cures. A sealer helps with soap and water absorption, but it doesn't waterproof a shower: that's done under the tile by your installer. Afterward, keep up routine cleaning as in cleaning a marble shower. Browse shower wall tile, shower floor mosaics and marble bathroom floor tile.

How do I seal a marble or stone backsplash?

A kitchen backsplash gets splashes of oil, tomato and citrus. An impregnating sealer, ideally an oil-repellent one, gives you time to wipe them up. It won't stop acid etching near the stove. Seal the tile and the grout lines once the installer says the grout has cured, wipe all excess off the face, and test first. Browse backsplash tile, or read our marble backsplash guide and travertine backsplash guide.

Can I seal a stone wall?

Wall tile sees fewer spills than a floor, so sealing is often optional, except in showers, kitchens and around fireplaces. Use the water-drop test to decide. Treat natural stone wall tile like marble tile. Manufactured veneer products differ by maker, so follow the maker's instructions for those. Browse wall tiles.

Can I seal marble pavers or outdoor stone?

Yes, but outdoors you need an exterior-rated sealer labeled for the stone, for sun and rain and, near a pool, for pool chemicals. Film-forming coatings trap water vapor, which is a cracking risk. We offer travertine pavers and pool coping. For outdoor cleaning and sealing, see caring for travertine floors, patios and pool decks.

How to seal tile and grout

How do I seal tile and grout?

Grout is porous, so it soaks up spills even when the stone doesn't. After the grout has cured as its maker directs, apply a grout sealer labeled for your grout with a small brush or applicator. Wipe any off the stone face right away, then let it cure. Mosaics have narrow lines, so work in small sections. Test first and check that the product is safe on marble. Epoxy grout generally doesn't need sealing, so follow the grout maker. The same goes for a kitchen backsplash: sealing grout lines there takes the same steps. Reseal grout when water soaks in instead of beading.

Should I seal marble before or after grouting?

Some installers seal porous or textured stone before grouting so the grout color doesn't soak into the stone face. Others seal after. Ask your installer which they prefer, follow the labels of both products and test on a spare tile first. You can read more in our installation guide.