If the tile is already there and if you don't want to remove the existing tile, then this situation is a little more challenging.
I gave some thought to this issue when I was doing my flooring at my new home. I had considered installing the tile in the bathroom through the builder and hard wood floor by outside vendor afterward. But after discuss with the vendor regarding to the wood to tile transition issue, I had both tile and wood done by the outside vendor together.
Well, if the tile is already there, here?s some options but make sure the height/thickness of the wood plank is very close with the level of the tile.
The installer can place a piece of hardwood plank parallel with the tile border like the first picture. The installer can tilt, adjust, trims the thickness of wood plank so it will make a level transition from hard wood floor to the tile.
Or you can add a mosaic tile trim at the border like the second picture for a smooth transition between tile and wood flooring.