I would because I have children who do things like make blueberry raspberry smoothies and forget to put the lid on the blender!

We sealed ours when it was installed. We used water-based Aqua Gold(?) sealer; sold to us by Artistic Tile when we got our backsplash tile from them. It's what they recommended, so we wanted to use their preferred sealer.

We used a solvent based sealer elsewhere (bathrooms, FR floor...). Probably could have used that on our backsplash as well, but didn't get/use it until a few years after the kitchen reno.

Thank you both--that was quick! I think I'll ask the tiler to seal then. Cat Mom, do you feel the water-based sealer does the job ok? Any stains?

I do remember Bill talking about a sealant that turned out to be quite toxic, or something,

Not sure why that would be a problem -- presumably you are not eating many things that have been stuck to your backsplash....

I think it's okay. Over our Wolf range, just above the vent, we'll get some discoloration that takes some elbow grease to remove (especially after long or high heat oven cooking). Vented grease or something. Otherwise it seems to clean up pretty easily. I rarely splatter onto the backsplash while prepping or cooking, so it's not much of an issue. The counters and floors are another story! LOL

Depends on your backsplash material. Ceramics,porcelain I've never sealed the grout, especially with 1/8' joints. And certainly never sealed the tile.