Email appending is a process to match and verify the customer data in the repository with actual information. Email appending, also known as e-appending, is a marketing practice to take the customer data, mostly first name, last name & postal address, and cross-check it with the vendor’s database to acquire their email addresses. Email Appending is a method of appending email addresses to the corresponding lead list. Email Appending also checks for any inconsistencies in the existing email addresses and replaces them if found.