How to Clean Tile Grout in the Bathroom (White Grout Restored)

Bathroom grout is porous and absorbs soap scum, mold, and mineral deposits that make it look permanently grey or black. With the right technique, you can restore white grout to near-original brightness.

What You'll Need

• Foxtrot Living Grout Brush with Long Handle — hard bristles designed specifically for grout lines
• Baking soda
• White vinegar or hydrogen peroxide
• RMR-86 Instant Mold and Mildew Stain Remover — for black mold stains in grout that won't respond to other methods
• JohnBee Spray Bottles
• Rubber gloves and eye protection (when using RMR-86)

Method 1: Baking Soda + Vinegar (Best for Regular Cleaning)

1. Make a paste of baking soda and water (thick enough to stay on vertical grout lines).
2. Apply the paste along the grout lines with your finger or a brush.
3. Spray white vinegar over the paste — it will fizz.
4. Let sit for 5–10 minutes.
5. Scrub with the grout brush using firm back-and-forth strokes along the grout line.
6. Rinse with warm water.

Method 2: Hydrogen Peroxide (Best for Whitening)

1. Apply 3% hydrogen peroxide directly to the grout lines.
2. Let sit for 10–15 minutes.
3. Scrub with the grout brush.
4. Rinse thoroughly.

Hydrogen peroxide is a mild bleaching agent that whitens grout without the harshness of chlorine bleach. Particularly effective on yellowed or grey grout.

Method 3: RMR-86 (For Black Mold Stains)

1. Ventilate the bathroom well — open windows and run the exhaust fan.
2. Wear rubber gloves and eye protection.
3. Spray RMR-86 directly on the black mold stains in the grout.
4. Watch the stains disappear in seconds — no scrubbing required for most stains.
5. Let sit 15–30 seconds, then rinse thoroughly with water.

RMR-86 is the most powerful mold stain remover available for grout. It works on contact and eliminates stains that nothing else can touch.

How to Keep Grout Clean Longer

• Seal grout annually with a grout sealer — sealing closes the pores and prevents staining
• Squeegee tile walls after every shower to remove water before it evaporates and leaves deposits
• Spray with diluted white vinegar weekly
• Clean grout monthly before stains have time to set

Frequently Asked Questions

How do I get grout white again?

For yellowed or grey grout: hydrogen peroxide applied and left for 15 minutes before scrubbing. For black mold stains: RMR-86 spray. For general dinginess: baking soda paste scrubbed with a grout brush. Sealing after cleaning keeps it white longer.

Can I use bleach on bathroom grout?

Yes — diluted bleach (1 part bleach to 10 parts water) whitens grout effectively. Apply, let sit 10 minutes, scrub, and rinse very thoroughly. Avoid bleach on colored grout as it can fade the color. Ventilate well when using bleach.

How often should I clean bathroom grout?

Monthly scrubbing prevents staining from setting. Annual sealing dramatically reduces how often deep cleaning is needed. Daily squeegeeing after showering is the most effective prevention habit.