There are a few different reasons for replacing a tub spout. Sometimes it is as part of a repair when the spout is leaking or stops diverting water to the showerhead. Other times it is for cosmetic reasons if the tub spout is old and has lost its finish or you simply want another finish or style. Whatever the reason before you replace a tub spout you need to determine what type of tub spout you are dealing with.
Here are the different types of tub spouts and instructions for removing them.
The first thing to do is to look under and around the tub spout. If there is a hole on the bottom or the side of the tub spout you have a clamp on spout.
Clamp on type spouts: There is usually an Allen screw up inside the small hole that is clamping the tub spout in place. Most likely you will need an Allen key that is the right size to loosen the fastening screw located under the tub spout. Sometimes there is a flat screw on the side of the spout instead. Unscrew the fastening screw counter clockwise until it is loose. Turn the tub spout left and right as you pull it out to remove it from the pipe. Then you can take the old spout in and get it matched up at the store if you want. Or you can order a replacement spout online if you know what type you need. The clamp on spouts are universal because they all clamp onto the copper tubing near the base of the spout, just make sure to get a diverter stem if that is what you need.
Also, make sure to get the finish you want because they all come in different types of finishes.
If you have looked all the way around the tub spout and there are no areas where a screw can be hiding then you have a screw on tub spout.