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How Telemarketers Get Your Mobile Phone Number

In May, I wrote about how easy it is to find online consumers' mobile phone numbers at websites like Intelius. A natural question from that blog post: how do these data-mining websites and telemarketers obtain consumers mobile phone numbers? That's a relevant question, since consumers have reportedly registered about 200 million phone numbers with the Do Not Call registry since 2004.

There is a good article at that answers this question. First some surprising statistics:

"... despite the registry, an estimated 150 million telemarketing calls are made each day in the United States, an estimated 20 percent, or 30 million, of which are potential violations..."

So, a lot of the calls you receive at home are potential violations if you have registered at the Do Not call registry. Many are not violations since there are a multitude of ways your mobile phone number can leak out to telemarketers and data brokerage companies:

  1. Debt Collection Agencies: will contact you whether or not your phone is listed in the Do Not Call registry. Debt collectors will contact you directly or will contact a family member to find your address and phone number.
  2. The United States Post Office: will sell for a small fee a box holder's residential address, if available.
  3. Social media sites: will display your phone number and e-mail, especially where many consumers haven't made their profile page private and accessible only by friends.
  4. Product warranty cards: when you register online or via snail mail that new product you've purchased, you have helped the manufacturer assemble a database of names, addresses, e-mails, and phone numbers that can be sold to marketers and data brokers
  5. Data brokers: regularly sell consumer information, including residential addresses, e-mail addresses, and phone numbers to telemarketers

What consumers can do to minimize this leakage of your mobile phone number:

  • Don't be so quick to disclose your mobile phone number. Ask yourself if you really want this company to know your mobile phone number. Maybe your-email address or landline phone number is enough
  • Register your mobile phone number at the Do Not Call registry, if you haven't already
  • Be careful about the sweepstakes and contests you enter. Read the fine print or contest terms closely, as that document will indicate whether the contest operators will sell your information to other companies
  • Read the privacy policy at websites you visit and have registered at. This document will indicate whether the website operator will sell your personal information to other companies
  • Read the privacy policy for mobile phone apps before you install the app. If the app developer does not have a privacy policy, then that should be a strong clue
  • If you owe money, know your rights regarding debt collection
  • You can file a complaint at the Do Not Call website

To read the full list of ways your mobile phone number can leak out to telemarketers and data brokers, see the article.

The author of the article suggested that consumers with the Droid and Blackberry brand smart phones use the PrivacyStar app to block and report unwanted telemarketing calls. I have not used this app and cannot verify its accuracy. If you use PrivacyStar app, let us know what you think of it.


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Samantha Cole

Basically, our mobile numbers do get spread whenever and wherever we give our numbers for registration. The best way to stop the leakage is to ask your phone company for advice, and to be more cautious with the organizations you deal with.

sell my mobile

Thanx for the informative post. Mobile no. leakage is a big problem nowadays. I've been a victim of such unwanted callers for a long time nd every time I received such an annoying call, I keep wondering how they get my number. It's really hard to identify sources frm. where they get my mob. no. I'll try to follow all the instructions to avoid further undesired calls.

Crystal Pena

Thanks for the information! I am worried that having your privacy is getting harder and harder these days..

Michael K. Molter

That is a good strategy think before you give your mobile number it is better to give your email address rather than your mobile number.I will take it in my mind.thanks.


No! it's much easier than this, i can generate mobile mobile numbers with a special application for any operator in the world, but can't get their names,occupation,gender,age,etc. but this is useless!anyways:s


Just some helpful information, if you want to block advertising and trackers on your internet browser check out this site and install do not track plus. On this site I blocked 7 tracking sites..


I believe my cell phone number was shared through the dating site I subscribe to. The "guy" be friended me and after a few email exchanges we agreed to share mobile numbers, but he never called!

Clark Anderson

It can be quite annoying when someone you don't know suddenly calls in the middle of a busy schedule just to sell some stuff. Thanks for posting this!



call me urgently!!!!!!!!

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