Well isn’t that confusing: the first link I get from Google for “transactional email” actually contains incorrect information! It’s not really about financial transactions at all, anymore. (Though e-commerce does happen to generate a lot of this kind of email, more on that later…)
Definitions, Synonyms, Examples
So what is transactional email? Coming from a MailChimp state of mind, you might simply think of it as “anything that isn’t bulk“. Basically, it is email sent to an individual based on some action. It could be:
- an action they took directly
- an action they were the target of or,
- perhaps even inaction on their part

A warm welcome sets the tone
For example, if a user signs up for your website, you should probably welcome them with a lovely email. Bam! That’s a transactional email. Signing up is the “transaction” in this case. Simple, right?
An example of an action happening to a user might be the familiar “so-and-so commented on your hooza-whatsit” alerts we all receive from our favorite social networking sites. In these cases the action was taken by other users, but the recipient was the target of the action, so they receive a notification email letting them know something of interest happened.
