Which column must be included in the CSV file used to create a DNC list?

The inclusion of the Phone number column in the CSV file used to create a Do Not Contact (DNC) list is critical because the main purpose of a DNC list is to specify which phone numbers should not be contacted in outbound campaigns. This column allows the system to identify and flag specific numbers that are associated with individuals who have opted out of receiving calls, ensuring compliance with regulations and respecting customer preferences.

Including just a Contact ID, a Name, or a Type column wouldn't fulfill the primary requirement of creating a DNC list because those elements do not provide the essential information needed to prevent contact. Without the phone number, there would be no way to enforce the DNC status on the actual contacts in the system, which could lead to potential compliance issues and damage to the business's reputation.