Found an interesting trick: Send a call to voicemail

[Backnblack]

I found that paying my bills on time is a good way to block bill collectors.

A concept that is foreign to some....

 

[takeshi]

You can also make your phone block calls using Google voice. When somebody you don't want calls they will get the " were sorry this phone is no longer connected or no longer in service" I can look for the walk through I posted awhile back if anyone wants it.

GV also allows you to flag callers in such a way that they go straight to voicemail and the voicemail is deleted without alerting you at any point. IIRC, the caller has to be flagged as spam versus blocking the caller.