How do I measure whether my journey actually increases conversions?

Add a Holdout Split element. It holds back a share of users at one point in the journey and compares their Conversion Goal completion with users who continued.

1. Define at least one Conversion Goal for the journey. Without one, the report shows a prompt to add a goal instead of numbers.
2. Place Holdout Split before the messages or steps you want to test and double-click it.
3. Set Share held out (1–20%).
4. Leave the Holdout branch unconnected: those users exit the journey and get nothing else from it. Connect In journey to the rest of your flow, then click Save.

Held-out users are excluded from this journey only. They can still get messages from other journeys and one-time sends.

To read the results, open the running journey, open the Holdout Split point, and find Goal uplift vs holdout. The report refreshes once a day, and the first numbers appear the day after the journey starts. For each goal, compare Conversion, in journey with Conversion, holdout and check Uplift. Act on it only when the badge says Significant. Not significant or Not enough data means the difference isn't reliable yet.

To see which users went to each branch, click Export users (requires the Personal data permission; data from the last 2 months).

For an account-wide holdout instead of one inside a journey, use Control groups.

Learn more: Holdout Split