A contrasting grout will highlight EVERY little imperfection in the tile installation and layout. A 1/16" variation in a joint that is only 1/8" wide is a 50% error and jumps right out at you.

If the layout is done poorly and you end up with little 1" pieces of tile in the corners, it will jump right out at you.

If your contractor is not a real pro, anything but white is asking for trouble.

If your contractor is not a perfectionist, you be back here crying like so many other people.

The pattern just isn't interesting enough that you need to highlight it. A simple wall of shiny white makes its own statement.

TL,DR: Use white.

Why don't you like white grout? If you believe it is harder to keep clean you are wrong about that. A high quality undsanded grout with latex additive in it will stay pretty damn white and look better than grays over time. Gray grout gets soap scum on it that you constantly need to get off to keep the color uniform.

If you just don't like the color of white grout then you need to be ready to live with little flaws like the above poster said.

Your current wall looks to have white grout. I see a white wall, not individual tiles. I like that look very much.

You bring up a good point about the plastic sheet walls. Can you test your options? Or keep looking at bathroom pics of both to see which you like better? I prefer when the grout is similar in colour to the tile. I'm not a fan of delineating every tile on a wall. What layout pattern have you chosen for your tiles? That will affect the look as well.

I always thought dark grout is mostly used in public restrooms worldwide because it hides dirt and because it is the cheapest and the oldest color available (cement+sand+water).

I'm not a tile expert but I do know that grout comes in quite a variety of colours depending on the make. Have you considered every viable option? Perhaps you need something between white and cool grey? There might be a "dirty" white that's just the shade you need. Look at Fresh Snowdrop below (09) and Winter White (29) below.

Ardex - Flex

Look at the white below. Not blinding white.

Mapei grout

If you're not sold on either of your two colour options, can you keep looking? Btw, in your inspiration pic, I like the grout between the tiles but not the look on the wall edges.

the first picture you posted is perfect. Driftwood? looks great.

Oyster gray is another one. Don't go too dark.

Mapei Frost with white tile. Very forgiving.

Of your three favourite combos, I'd go with the first, the lightest. (Is your bathroom lighting done? Make sure you check your samples in the same lighting.)

I still find the grey too contrasting but that's my preference. If it were my bathroom, I'd be comparing White Dove, Bright White, Snow White and Bleached Wood.

This afternoon, I noticed the subway tile in a restaurant bathroom and quickly snapped a closeup to show you a "white" grout with white tile. (Not saying that's a source of high end design inspiration but the wall looked like a white wall to me, not stacked tiles.) Should have taken a pic of the whole wall to show you the effect but someone came in and I didn't want to seem creepy. :P

just take some leftover tile and glue it to a board. try the different grout samples. let dry. see which one you like best.

I'd do as Beth suggested. The same way it's a good idea to paint large poster boards and move them around a space to check colours in different light, I think testing grout is worth the time.

Thanks! The tile is Middleton Square in oxford white by Marazzi. They have a lovely reflective wavy surface. Tiles are large, 4 1/4" x 12-7/8". I'll grab some photos for you tomorrow.

Before and after with rolling fog Home Depot grout

Looks fantastic! Thanks for sharing pics of the completed project.

Thanks! I could have taken some better photos, and we still haven’t made the mirror we are going to use, but you all get the picture ;)

@Slough Shark I love how your bathroom came out!! That grout color looks great with your subways, just the right amount of contrast. what color grout did you use for your floors?

@Slough Shark we are just getting started with the master bath in our new (budget) build- although we have hired a reputable tiler to do the tile work. 4x16 white glossy subways for the shower walls and grey pebble mosaic for the shower floor. Bathroom floor tile is a dark grey and I am struggling to pick a grout for the floor tile. I want to use the same color for the mosaic and hexagon floor tile. Looks like your floors might be about the same color... could you post a pic of the floor tile? Im considering pewter or dove gray from custom building products.

i am now debating choosing rolling fog instead of platinum for the subways after seeing your results!!

Hi! Excuse the poor quality photos of the bathroom, the lighting is not great. We used charcoal grey for the floor grout! But it lightened up considerably, which I actually like. The same happened to my parents floor grout when they used charcoal. And I still, one year after our reno, LOVE the rolling fog. I think I would have regretted going platinum OR darker for the grout. Happy reno-ing!

@Slough Shark thanks for the information!! We already grouted the guest bathroom with dove grey and I love it! I think our floor tile is just a tad lighter and that grout color seems to match the tile quite well. I think we will end up using the Dove grey in the master for both floor tile and the shower floor pebibles. The pebbles are a little lighter then the floor tile so hopefully it will still look ok. We have decided to go with rolling fog for the white subways though. So glad I ran into this thread!!

here is a pic of the dove gray in the guest bath.

One more question, was your charcoal from custom? it almost looks lighter then the dove gray In your photos

I LOVE your floor tiles. Great shape! I have attached a photo of the brand we used for charcoal (from Home Depot). It initially came out so dark grey it looked black, but lightened pretty quickly. It could be because of the mineral content in our water here? I wash the floors often, so that could just be mineral build up. It doesn’t bother me though, otherwise I would get one of those “grout pens” to darken it again. Which I may do for a freshen up!