Good to know: this takes two parts. First you map a custom field so AEvent knows what to send, then you add a Timeline action that actually fires the update to your CRM or ESP. You need both. AEvent also sends attendance data only for people who attended, so non-attendees are skipped automatically.

Open your campaign, go to Integrations, and open the settings for the CRM or ESP you want to update (for example ActiveCampaign). Scroll down to Custom Fields (Personalization).

Click Create Single Field to add one field, or Create System Fields to add a set at once. Give the field a name, such as AttendanceTime, then click Create.

Open the field you just added and set it up:

1. Value type: Attendance Info.

2. Format: the attendance data you want to send. Choose Attendance Time (seconds) for the total time watched, or one of the many Attended date and time formats. See Attendance format options below for the complete list, and pick whichever matches how your CRM or ESP stores the field.

3. Event: if your campaign has more than one event, choose which event's attendance to send, such as Main Event.

Save the settings.

Mapping the field tells AEvent what to send. A Timeline action is what actually fires it to your CRM or ESP, so without this step nothing syncs. In your campaign's Timeline, create a new action:

1. When: pick when it fires, such as one day after the event at a set time. Sending after the event means each person's attendance is final.

2. Event: the event whose attendance you're sending, such as Main Event.

3. Who: the audience, such as Registrants (attendees still get their real value, and non-attendees are skipped).

4. What: choose AEvent Functions, then set Actions to Update Custom Fields (CRM/ESP).

Click Create. New to the timeline? See our Timeline Action Builder Basics guide.

Register for your own event with a test contact, attend for a few minutes, and let the action fire at the time you set. Then open that contact in your CRM or ESP and confirm the attendance value landed in the field you mapped.

The Format dropdown offers one total-time option plus a range of date and time formats. Attendance Time (seconds) is the total time the person watched. The Attended formats show when they joined (not when they left), as a date or clock value. Times use your account's time zone or a fixed zone, never the attendee's own zone. The examples below show how each renders for a sample attendance on July 3, 2026 at 9:31 PM EDT, and each contact receives their own real value.

Total time watched

Date joined

Date and time joined

Time joined, in your account's zone (renders in the time zone set on your AEvent account, shown here for a US Eastern account, in four styles):

Time joined, in a fixed zone (always converts to that specific zone, whatever your account is set to):

Single value

Nothing arrives in the CRM or ESP. The most common cause is a missing Timeline action. The field mapping alone does not push anything. Add the Update Custom Fields (CRM/ESP) action from Step 4, and check its When has already passed.

The field is empty for some contacts. Those people did not attend. AEvent only sends attendance data for actual attendees, so non-attendees are skipped by design.

The value isn't formatted the way you expected. Open the field and change the Format to match what you want, such as Attendance Time (seconds) versus one of the Attended date formats.