How to Pass Attendee Details in the Call-to-Action Banner Link for a Virtual Event in Zuddl

Last updated: September 9, 2026

What This Does

The Call-to-Action (CTA) banner is the button attendees see in the engagement panel during a event. You can set it up so that when an attendee clicks the CTA button, Zuddl passes their standard registration details and the event ID to the destination link. An external form — for example a "Book a demo" form — can then pre-fill itself, instead of asking the attendee to type details they have already given you.

Note: Only the standard registration fields listed below are passed. Custom registration fields are not passed in the CTA link.

Before You Begin

You need organizer access to the event setup.
Keep the destination URL ready. It must start with https://.
Check that the destination form or scheduling tool (for example Calendly or HubSpot) can accept details passed in a link, and confirm who manages that form.

Steps

Go to the Venue Setup > Engagement page of the event setup.
Toggle on the Call-to-Action banner.
Enter the Banner text and the button Text.
Choose the Button type:
- Redirect to: opens the redirection URL in a new tab.
- iFrame: opens the redirection URL in the sidebar as an iFrame.
Enter the Redirection URL.
Select the Add registration standard fields and eventId to this URL checkbox.
Click Save.

What Happens Next

When an attendee clicks the CTA button, their registration details are added to the destination link, and the destination form can use them to pre-fill its fields. This works for both button types — the new-tab redirect and the embedded iFrame.

Standard fields that are passed

The details come from the attendee's own registration profile for that event:

Field	Value
`eventId`	The Zuddl event ID
`firstName`	Attendee first name
`lastName`	Attendee last name
`email`	Attendee email address
`phoneNumber`	Attendee phone number
`designation`	Attendee job title / designation
`company`	Attendee company
`bio`	Attendee bio
`country`	Attendee country

Notes

Your own link settings are kept. Tracking parameters you have added to the link, such as utm_source, continue to work as before.
The attendee's details take priority. If your link already carries a fixed value for one of the fields above, the attendee's own value is used instead.
Blank fields are not sent. If an attendee has not filled in a field during registration, that field is simply left out of the link.
Enter the full link. Always add the redirection URL starting with https://. If the link is entered without it, the CTA still opens, but the attendee's details are not added.
The destination form needs to accept the details. Zuddl passes the fields along; your form or scheduling tool has to be set up to read them and map them to its own fields. Share the field names in the table above with whoever manages that form.

Warning: Attendee details are shared with the destination site. Because personal details are passed to an external site, enable this only for destinations you trust and that your privacy policy covers.

Troubleshooting

Symptom	What to check
Nothing is pre-filled on the destination form	Check that Add registration standard fields and eventId to this URL is selected and the banner was saved.
Only some fields are pre-filled	Those fields are blank on the attendee's registration profile — blank fields are not sent.
The details are passed but the form is still empty	The destination form is not set up to read these field names, or it expects different names.
Nothing is passed at all	Check that the redirection URL starts with `https://`.

How to Enable Call-to-Action for a Virtual Event in Zuddl