Hi Alex, welcome to the community.  Great question, one that I’ve asked before. 

Short answer, it will not send to those 12,000 members if you created the flow AFTER the segment was created. 

Now if you did want the flow to trigger for those 12,000, you can use the back-populate feature.  Here’s the help article with more details on how that works.

Hope that helps!

Hi @Sleipnir , 

Welcome to the Community, I agree, this is a great question! @Mailbox Manny is spot-on, a Segment-Triggered Flow will only fire once it is triggered, meaning someone new is added to the segment. It will not push everyone through the Flow if the segment was created before the Flow. If you want to  Back-Populate Your Flow and retroactively send everyone through the Flow, I would Back-Populate relative to the moment when you click the “Back-Populate” button. This will capture your entire segment and push them through the Flow vs. scheduling the Back-Populating back to a specific time frame as this will only capture users in the segment who joined around that designated time. 

It’s also important to note that in Segments there can be a delay of up to 1 hour before Klaviyo “processes” that the subscriber is eligible to enter the Segment based on the Segment's definitions, so if you don’t see your segment automatically updating and a user receiving the Flow email in mind, this is the reason. 

I would recommend checking out these Community Posts made by fellow users asking similar questions about troubleshooting Segment-Triggered Flows and more insight into how they function!

Thanks for being a part of the Community! Let us know how this works for you! 

Best,

Taylor  

Hello everyone,

Thank you for your replies, great help!

Best regards,

Alex