I just got a call which I will add or have already added to my block list.  I will now get no ring but I will be able to get list of blocked calls on my phone.
I have the Panasonic cordless telephone  Model kx-tg6842b (2 handsets)
You can block 250 numbers plus kill the one ring that existed on earlier models that only allowed 30 blocked numbers.  The one handset model sells for $70 at Amazon.

I also got recently the Call Blocker version 2.2 which allows blocking 10 area codes plus 1500 phone numbers.