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Email Service Provider (ESP)


An email service provider (ESP) allows users to send email campaigns to a list of subscribers.

Email service providers are technology companies that make it easier for people to build email lists and send emails. As email marketing has become a more popular marketing channel, more email service providers have sprung up to provide differentiated services.

At the most basic level, an ESP needs to do two things: store email addresses and send emails.

A more advanced email service provider offers additional features, including:

  • Dynamic content in emails
  • Email and marketing automation
  • Lead capture forms
  • A/B testing of email subject lines and email content
  • A/B testing of entire automations
  • Website tracking, to collect more information about subscribers
  • Segmentation based on what subscribers are interested in

Which is the best email service provider?

According to Venture Harbour, “Once an underdog, ActiveCampaign is now one of the most popular email marketing tools with over 130,000 small businesses customers.”

Learn more:

Is Gmail / Outlook / AOL an ESP?

No. Despite providing access to your email, they are not what email marketers would refer to as an ESP as they do not allow you to use email contact lists or send campaigns to subscribers.

What does ESP stand for email?

Email Service Provider

What is an example of an ESP? What are the various email service providers?

  • ActiveCampaign
  • Hubspot
  • Mailchimp
  • Klaviyo
  • ConvertKit
  • Campaign Monitor

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