Mailchimp was founded in 2001 by Ben Chestnut and Dan Kurzius. The company started as an email marketing service for small businesses. In 2012, Mailchimp acquired Mandrill, a transactional email service, for $250 million. In 2016, the company announced that it had reached 10 million customers.
Constant Contact was founded in 1998 by two entrepreneurs, Bill Wagner and Hari Ravichandran. The company's original mission was to help small businesses grow by providing them with easy-to-use email marketing tools. In the early days, Constant Contact offered only a handful of features, but the company quickly grew in popularity due to its simple and intuitive interface. Today, Constant Contact offers a wide range of features, including email marketing, social media marketing, event management, and survey creation tools. The company has also expanded beyond the United States, offering its services in more than 100 countries worldwide.
Mailchimp is a more popular and user-friendly platform, while Constant Contact is more expensive but offers more features.