Well, that depends. If it is a regular corded phone, then the power used over the phone lines is minimal (in the order of milliwatts). If you're referring to a cordless phone, the answer is written on the power supply. Just look on the wall wart, there will be an output rating in either amps or watts. That is the maximum power it can use. It probably uses about half to three quarters of that on average.
It depends for exaple some chargers have a light on it, that takes energy not much but it does other then that no.
When the phone is turned off, the battery provides a trickle of power to maintain the memory in the phone.
Your phone dies because in the technology world you need battery and power to use your electronic device. So it dies because you've used it so much so the technology power just goes out.
depenf on phone& battery capacity also how long we use the phone.
All appliances and cell phones use 'power' even when not in active use.
because it's a voltage that carries the phone signal on it, and that's what your phone runs off - unless it's one that also has a power connection - ie cordless, memory bank etc etc
wind power
The power button.
If you are looking for an office telephone, then a VOIP phone will be your number one choice. However, if your office loses power, then you will not be able to use your VOIP phone.
That depends on how much you use the phone.
About 50 Watts.
How to find out how much power articles use? In Canada