"Mailchimp" is the trade name of its operator, Rocket Science Group, an American company founded in 2001 by Ben Chestnut and Mark Armstrong,with Dan Kurzius joining at a later date.

[5] The platform was named after one of their most popular e-greetings card characters, earning a few thousand dollars monthly.

[11] Mailchimp later announced its plans to shift from mail distribution to offering a full marketing platform aimed at smaller organizations.

[13] With founders Armstrong and Chestnut starting the company without outside funding or plans to go public, and never bringing on any outside investors thereafter, Mailchimp is considered an example of a successfully bootstrapped startup.

[14][15][16] After turning down repeated acquisition offers for 20 years, Bloomberg reported on August 31, 2021, that Mailchimp was talking with Intuit about being acquired.

[21] Another ad became memorable for its inclusion of an unscripted mispronunciation of the company's name – "MailKimp" – as spoken by a 14-year-old girl from Norway waiting in line for an iPhone 6.

[26] In February 2016, Mailchimp announced it was merging Mandrill transactional email service into Mailchimp as an add-on feature and gave customers 60 days' notice to switch to the new pricing structure or find an alternative service platform.