[sgdread]

Here's what you do to significantly reduce telemarketers calls:

1) Go to https://www.donotcall.gov/ and register in the National Do Not Call Registry

2) Wait 31 day (it takes some time to propagate this information to callers)

3) Start reporting unwanted calls via link above

I have not received a single telemarketer call over a year since I started doing that.

FTC is also very good at dealing with collection agency calls if you are not the person they are trying to reach. I received personal apologies from ERC after filing complaint through FTC website.

[cimmanom]

There are some telemarketers who use the DNC registry as a source of lists of numbers to call. In particular, overseas call centers that are not subject to regulation. You're more likely to get scam calls this way.