We are registered with TPS. It only stops the legitimate businesses who go to the trouble of checking their purchased lists against TPS. It doesn't stop the rogues.
One of the biggest issues is that BT OpenReach still allow CLI (Calling Line Identity) spoofing. At one time, they were saying that once the 21CN went live (i.e. Fibre to the house) they would be able to prevent spoofing. Seen no sign of it so far and we have been fibre for 2 years now. A relatively few legitimate businesses have a reason to spoof CLI from their IP (Internet Protocol) connected off shore call centres. And these people (think banks and utilities in the main) would, I am sure, pay for the privilege.
