1) When we had AT&T, we had a service that forced any caller – who did not provide their identity for caller ID – through a separate system. The system would make them say their name into the phone, and the system would call us, let us know who it was, and allow us to take the call or not.
We have since nuked that option because we have Time-Warner, but it was pretty nice to have.
2) We are on the national “do not call” list.
3) Sometimes I just interrupt whatever they are saying with a “no thanks” and hang up, not bothering to listen at all.
4) We have an unlisted number and caller ID. I don’t answer the phone when it is obviously a sales call, but if the same number calls over and over, I answer and …
5) I first ask “who is calling” and as soon as they say who they are, I interrupt them with an “excuse me” and say the magic words. You can hear their dejection over the phone. They immediately know there is no sales technique they can use – legally or psychologically – to get around them. You can hear the dismay in their voice when you say them and they reply “I’ll be glad to do that.” The magic words are “please take me off your calling list.” Just say that, wait for them to confirm that they will and hang up.
It is also rewarding to answer the question “Hi. My name is x with x. How are you today ?” with “please take me off your calling list.”
Sometimes, you will get called back as it takes some time for the database to update, but there are fines if they do so make sure they know you have already asked to be taken off the list.
6) There is always the “Seinfeld” way:
Jerry: Now isn’t a good time but if you give me your home number I’ll call you back when it is more convenient.
Telemarketer: (not heard).
Jerry: Oh. You mean, you don’t like people calling you at home ? Well, neither do I …