Which Zuddl Emails Respect Unsubscribe Preferences (Operational vs. Preference-Respecting)
Last updated: July 10, 2026
What This Does
Zuddl sends two kinds of Standard Communication emails: preference-respecting emails, which are suppressed when a recipient has opted out of the relevant category, and operational / transactional emails, which are always delivered even if the recipient has unsubscribed. This article lists which emails fall into each group so you can predict whether a given email will reach an attendee who has unsubscribed.
Note: Only the emails in Table 1 are checked against an attendee's unsubscribe preference. Everything else is treated as operational and is sent regardless of unsubscribe status, because it carries information the recipient needs to attend, transact, or manage their participation.
Before You Begin
Unsubscribe preferences are set per attendee, per event — an opt-out on one event does not carry to another.
Attendees opt out by category: Pre-event, Live-event, Post-event, Important updates, and Invitations.
A category opt-out only suppresses emails that belong to that category and are listed in Table 1 below.
How unsubscribe works in Zuddl
An attendee opens the unsubscribe link in any Zuddl email or the preference options for the event.
They opt out of one or more categories (Pre-event, Live-event, Post-event, Important updates, Invitations).
Zuddl records the opt-out for that recipient on that specific event.
For every future send, Zuddl checks the recipient's preference only for emails in Table 1. Matching emails in an opted-out category are suppressed; all other (operational) emails continue to send.
Table 1 — Emails that RESPECT unsubscribe status
These are suppressed when the attendee has unsubscribed from the relevant category.
Category | Purpose | |
|---|---|---|
Pre-event reminders | Event reminder — 7 days to go | Upcoming-event nudge |
Pre-event reminders | Event reminder — 1 day to go | Upcoming-event nudge |
Pre-event reminders | Event reminder — 1 hour to go | Upcoming-event nudge |
Pre-event reminders | Event reminder — 5 minutes to go | Upcoming-event nudge |
Post-event | Thank you for coming | Sent to attendees who joined |
Post-event | We missed you | Sent to registrants who did not attend |
Important event updates | Event cancelled | Notice that the event was cancelled |
Important event updates | Registration modified | Notice that registration details changed |
Important event updates | Resend calendar invite | Re-sent calendar invitation |
Important event updates | Resend group calendar invite | Re-sent group calendar invitation |
Invitations | Event series consolidated invitation | Invitation/confirmation for an event series |
Custom communications | Custom email | Organizer-authored marketing/announcement blast |
Abandoned registration | Abandoned registration — immediate | Nudge to complete an unfinished registration |
Abandoned registration | Abandoned registration — 1 day later | Nudge to complete an unfinished registration |
Abandoned registration | Abandoned registration — 4 days later | Nudge to complete an unfinished registration |
Abandoned registration | Abandoned registration — 7 days later | Nudge to complete an unfinished registration |
Table 2 — Operational / transactional emails that IGNORE unsubscribe status
These are always delivered, regardless of unsubscribe preference.
Category | Representative emails |
|---|---|
Registration & approval | Registration confirmation · Registration approved · Registration rejected · Registration incomplete · Registration pending approval · Registration PDF download |
Invitations (single event) | Event invitation · Decline invitation |
Ticketing, payments & invoices | Ticket purchase confirmation · Ticket cancellation / refund (partial & full) · Ticket re-assigned · Order modification confirmations · Self cancellation · Transaction cancelled · Ticket payment reminder · Resend ticket invoice / receipt · Zuddl invoice PDF · Cancellation invoice PDF |
Sessions & agenda | Session added / updated / cancelled on your agenda · Session reminders · Session starting |
Booths & sponsors | Booth owner invite · Sponsor booth owner invite · Booth joining request accepted / rejected · Booth leads export · Thank you for visiting booth |
Certificates & badges | CPE certificate · Badge |
Account & housekeeping | Forgot organization identifier · Custom domain ready · Bulk import completions · Quota-usage alerts · Event-series registration confirmations |
Tip: Table 2 shows the functional grouping of representative emails. Zuddl sends 100+ operational email types in total, and all of them bypass the unsubscribe check.
What Happens Next
Once an attendee opts out of a category, Zuddl automatically stops sending the Table 1 emails for that category on that event. The attendee will continue to receive operational emails (Table 2) such as registration confirmations, tickets, invoices, and session updates so they can still attend and transact.
Notes
If an attendee reports missing a reminder or thank-you email, check whether they unsubscribed from that category on that event — this is expected behavior, not a delivery failure.
Transactional emails (confirmations, tickets, invoices) cannot be suppressed via unsubscribe; they are always sent.
Custom email blasts respect the unsubscribe preference, so opted-out recipients will not receive organizer marketing/announcement sends.
Unsubscribe is scoped to a single event; the same person may still receive emails for a different event unless they opt out there too.