A bulk email service allows you to send email communications to large lists of multiple recipients by incorporating email into your applications. You can send one email to many people, or a unique email to each person on your list with a bulk email service. Depending on the provider, you can send unique emails to each recipient by providing a template for substituting information (such as a name).

An email service provider (ESP), like MailGoes, is a company that provides bulk email services and email marketing tools.