Similar to the gap that can exist between your wall tile and tub you may have a space between the floor and your bathtub.
Large gap between floor tile and wall.
For smaller tiles is advisable to use small spacers.
Current trends are moving towards leaving much smaller grout lines between tiles.
Caulk between the wall and tile.
Never fill this gap with grout because tile grout is not flexible.
Caulking is the best choice for this application.
Upon removing the old cauld discovered that the previous owner basically filled a 1 inch deep and 1 2 inch in height gap between floor and wall with a lot of caulk.
The large format 18 inch tiles should have inch space in between.
Grout between the tiles.
As with any other gap near your bathtub you ll want to close the opening to prevent any possible water damage or the onset of mold and mildew.
Instead fill it with an elastic material capable of sustaining the movement of the floor and the movement of the wall.
These gaps exist between tiles that are on the floor as well as between tiles where the floor and the wall touch.
As the tiles increase in size a larger gap becomes acceptable.
I have attached a picture to give a better idea could someone please tell me what the best way is to fill these gaps and what material i should use.
The overall finish of your job really does depend on your own personal style.