"Thank you for joining us yesterday" is a fine email to send to someone who joined you yesterday. Sent to a full registration list, it reaches a meaningful number of people who did not, and it tells them you are not keeping track. The fix is not better copy. It is sending different emails to different people.
One list, three groups
People who did not come. Check-in data across more than 1,070 events put the median no-show rate at about 20%, and about 28% for free events.1 At a free event of 500 registrations, that is roughly 140 people about to be thanked for attending.
People who came but skipped the programme. Session check-in data from 411 events found that at the median event, about one in four people who checked in at the door never checked into a single session.2 Perhaps they came for the networking, the exhibition or the people. Sending them slides from talks they did not attend misses the point of their visit.
People who attended sessions. At the median event they attended 5.5 sessions each.2 They are the group most likely to want slides and recordings, and to tell you what to change.
What to send each group
Write all three before the event, not after. The day after a conference nobody has the energy to draft three versions, which is exactly how one generic email gets sent. Drafted the week before, with placeholders for the recording link and the next date, follow-up becomes a send rather than a writing job.
If you also capture leads for sponsors or exhibitors, that is a fourth flow with its own owner, and it belongs with them rather than in your attendee email.
The survey
Measuring satisfaction is standard practice: in the ICE benchmarking report on in-house corporate event teams, 76% measured it.3 The risk is not skipping the survey. It is sending one so long that it measures patience.
Ask what you will act on. Would you come again? What should we keep? What should we change? One open question. If a question would not change a decision for the next event, it does not belong. Then close the loop: the next invitation that says "you asked for longer breaks, so we added them" does more for response rates than any subject line.
Match the survey to the group, too. Session attendees can rate the programme. People who came but skipped every session cannot, so ask them one thing only: would you come again, and why. Their answer often tells you more about what the event is for than the session ratings do.
Satisfaction is one number. If leadership will ask whether the event was worth it, decide in advance which measure answers that; we separated the three things people mean by event ROI in measuring event ROI.
Timing, honestly
We looked for solid public data on when to send post-event follow-up and found vendor claims that contradict each other, so we are not quoting any of them. What we would defend without a citation: send while people still remember the event, which in practice means within a day or two, and send the no-show email at the same time rather than as an afterthought.
Before you press send
Consent. Follow-up about the event they registered for is part of the reason they gave you their details. Adding them to an unrelated marketing list is a different purpose, and under India's DPDP Act it is worth checking against the consent you collected. Our DPDP guide for organisers covers this.
Deliverability. A post-event send usually goes to the full list at once, which makes it one of the largest sends of the whole event. If your domain is not set up properly, it is also the one most likely to land in spam; see why event emails land in spam.
When the alternative wins: after a forty-person executive dinner, a short personal note from the host to each guest beats any segmented sequence. The three-group approach is for events too large to write to everyone by hand.
Where Aurentex sits
The three groups above come from three records: who registered, who checked in, and which sessions they attended. In Aurentex those sit together (session-by-session attendance is on Premium), with the email builder and email tracking alongside, so the lists come from one place rather than three exports matched by hand. Your first event is free, and its check-in data is enough to send your first properly split follow-up.
Common questions
Should everyone get the same follow-up?
No. About one registrant in five does not come,1 and about one in four of those who do never enters a session.2
What should the no-show email say?
Not thank you for coming. The most useful thing from the event, and the date of the next one.
When should I send it?
Within a day or two, while the event is fresh. We found no reliable public data on exact timing.
How long should the survey be?
As short as the decisions it informs.