Transactional email with SMTP - rate limit and tracking


we are planning to use the transactional email add-on and we have few questions.

Is there some rate limit for the smtp service?
Where the marketing department can create lists of users based on email events?
Do you track just email opening or every single link clicked on it?
Do you decorate the HTML content with some sort of opt-out link?




  1. The rate limits are just for the HubSpot APIs. 10 requests/second and 40k calls/day
  2. They can create those lists in the lists tool in HubSpot.
  3. Here are the event types that we track.

  1. Lastly, as these are transactional emails and not marketing emails we do not include an opt-out link.


Hi @pmanca,
for the first point, I’m talking about the SMTP service not the APIs.
Are there some rate limits for the SMTP too ?


@simone The SMTP service is exposed publicly through an API So all the normal API limits will apply.