How close to tile to the toilet HOLE?

[vdotmatrix]

I am getting ready to tile the bathroom floor and was wondering how close to the toilet hole should I tile and at what point so I have to use an extender ring when adding tile to the existing floor in the bathroom?

It's sometimes better to be lucky than smart.

[LazyPup]

You can tile right up to the edge of the hole. When properly mounted the underside of the closet flange should sit flush with the finish floor and the top of the flange will now be approx 3/8" above the finish floor..

The plumbing code prohibits the top of the closet ring being flush with or recessed below the finished floor.

.see illustration below