The Do Not Call Registry (DNC) is a federal government/FTC phone number database that allows users to register their home and cell phone numbers to prevent unwanted sales calls from telemarketers and other companies.  Once a number is registered with the DNC, it can take up to 31 days to put an end to sales calls to the number. Once that time period has ended, companies selling something are no longer legally allowed to contact you. Note that, unless you opt to remove your number from the DNC list, it will permanently remain on it (previously, numbers would only stay on the DNC list for five years.)  In addition to adding phone numbers to the DNC registry, users can also report unwanted calls.  However, the DNC database can’t protect you from all unwanted calls -- only those including a sales pitch. However, you can tell these companies that you are on the DNC list, which means they’re contacting you illegally.  You’ll still be able to receive:  Calls from illegal spammers Companies that you’ve done recent business with Political, charitable, and debt collection calls  Survey calls Informational non-sales calls