What's New in Sailthru

June 4, 2025

Transactional Message Cohorts - Now Available

Background

High-volume senders often use the Sailthru API to send various types of transactional messages. However, analyzing performance across these different transactional types hasn’t always been easy..

Solution

Sailthru is introducing a new way to group transactional messages sent via the /send API. We’ve created 10 predefined Transactional Message Cohorts that customers can assign to their transactional messages. This allows for better categorization and comparison of performance across common message types. The cohort value will be included as part of the X-Feedback-ID header.

Note: These cohorts are predefined by Sailthru. Please contact support to have this enabled.

What this looks like in Sailthru:

Example send:

{
  "template" : "My Template",
  "email" : "user@meetmarigold.com",
  "fbl_cohort": "cohort0"
}

For more information, see the send API documentation.