From the workshop. This first appeared in the build log of Privacy Guardian, a tool we are building to find and remove personal data from people-search sites. It has not launched.
Blocking numbers does not work. You block one, and the next call comes from a different number, often one spoofed to look local. That is not you doing it wrong. The economics of the operation make blocking one number at a time pointless.
What reduces the volume is cutting off the supply of your number. Here is the sequence, in order of effort against effect.
1. Register on the Do Not Call list
Free, quick, and worth doing first because it costs the least.
It will not stop the calls you are most annoyed by. Outright scam operations ignore the registry, since they are already breaking several laws. What it does stop is legitimate telemarketing, which is a real share of the volume for most people, and it gives you standing to complain about a company that should know better. The FTC gives companies up to 31 days to stop calling a newly registered number.
2. Turn on your carrier's spam filtering
The major carriers offer spam call filtering, and it is often not switched on by default. It works on the network rather than on your handset, so it catches calls before your phone rings.
Phones can also send calls from numbers that are not in your contacts straight to voicemail (on an iPhone the setting is Silence Unknown Callers). It is a blunt instrument and a remarkably effective one, if you can live with the trade-off.
3. Remove your number from people-search sites
This is the step most people skip, and it is the one that addresses the cause rather than the symptom.
Your phone number is listed next to your name and address on free people-search sites, and those listings are scraped constantly. Every removal is one fewer place a calling list can be built from.
It will not produce an overnight drop. Lists already sold are already in circulation. What it does is slow the rate at which your number lands on new lists, and over months that compounds. Start with the largest sites, which rank for your name and which the smaller sites often buy from. What you can actually remove has the bigger picture.
4. Stop feeding it
A lot of spam traces back to a number given away voluntarily: a loyalty card, a checkout, an online quote form, a sweepstakes entry, an app that wanted a phone number for "account security" and then shared it.
Two habits help more than they sound like they would:
- Use a secondary number for anything commercial. It absorbs the damage.
- Leave the phone field blank when it has nothing to do with the transaction. It is optional far more often than it looks.
What does not work
- Pressing a key to be removed. Answering at all confirms a live person, and the removal option on an illegal robocall is not a removal option.
- Answering to tell them to stop. Same problem. The most valuable signal you can give a spam operation is that a person answers this number.
- Blocking one number at a time. The numbers are disposable and often spoofed. You are blocking an address that was never real.
A realistic expectation
Do all of the above and the volume falls over the following months. It does not go to zero, because your number exists in places nobody can reach.
The thing to keep in mind is that this is a supply problem. Every call is downstream of a list, and every list is downstream of a source that published your number next to your name. You cannot get them all. You can get most of them, and then check now and then that they have not put you back, which they will.