Optimal send time prediction

Optimal send time prediction calculates the best hour to reach each customer. The time is based on their past campaign engagement, so every message lands when they're most likely to interact.

Packaging

If you're unsure which packages you have, contact your CSM.

How optimal send time prediction works

Optimal send time optimizes for clicks by default. The previous "optimize for open vs. click" selector has been removed because open event data can be unreliable. When click data is insufficient, optimal send time uses opens as a fallback.

The prediction relies on historical campaign event data. There's no minimum number of campaigns required, but accuracy improves with every campaign. A single click at 8 AM already sets 8 AM as that customer's predicted send time, and the model continues to refine this as more data comes in.

Optimal send time prediction workflow

1. Go to Analyses > Predictions, click + New prediction, and select Optimal send time.

2. Select the channel to optimize send time for. Select from the following options:

   • Email
   • SMS / MMS / RCS
   • All channels: Used to set universal send time.
   • Other: Used for custom channels, for which you specify the event and filter. For example, any campaign_open where channel = WhatsApp.

3. Set the default send time. This serves as a fallback for customers without a calculated optimal send time. 0 represents midnight. Optimal send time is always calculated in UTC-0. The timezone defined in user settings doesn't affect it.

   

4. If the prediction is part of an initiative, mark it as a global object to display it in the customer profile. Click the Initiative icon next to the prediction name and check the Global object box.

   

5. Click Save, then Start to launch the calculation.

The calculation typically takes only a few seconds. The Results tab won't be populated for this prediction type. To review results, check the optimal send time value on any customer's profile, or create a report to view optimal send times across your audience.

Use the optimal send time property

The optimal send time attribute can be used across:

• Segmentations: Filter customers by optimal send time to build time-of-day audiences. For example, evening-only email campaigns.
• Scenarios: Use a wait node to hold each customer until their optimal send time before triggering the next message.
• Reports: Compare click rates across send time buckets to validate whether timing improves engagement.

Limitations

Custom event tracking not supported

Optimal send time uses default campaign events. If you use webhook-based channels with custom event tracking, those events aren't captured by the predefined channel options. To calculate optimal send time for these channels, create a separate optimal send time prediction and select Other as the channel. You can then specify the event and filter directly—for example, any campaign_open where channel = sms.

Related articles

Optimal send time in scenarios and campaigns: Learn how to use optimal send time predictions in scenarios and campaigns.

Prediction use cases: Explore real-world examples of how predictions can personalize customer experiences and drive engagement.