If a contact need a to be deleted, follow these steps:

1. In the Sales Module, click on the Customer tab and search for the company where the contact you wish to delete works.
2. Click on the Company Name.
3. Click on the Contacts tab then select the name of the person you want to delete.
4. Click on Delete Contact.
5. If the contact is associated with an estimate or order, the contact will be marked as inactive instead and will show up under Inactive Contacts below the Active Contacts list.

NOTE:  Each account must have a minimum of one contact. Also, you cannot delete a contact that is currently set as a company’s Primary or Billing contact.