It is possible to add a cell phone to the National Do Not Call Registry. Specific directions on how to add a cellular number to the list are available on DoNotCall.gov.
To add a number to the National Do Not Call Registry, the website prompts a user to enter up to three different phone numbers and an associated email address. It then sends an email with a link that must be clicked on within 72 hours in order to successfully register the phone numbers. This process is completely free and can be used to register either home or mobile numbers.