> ## Documentation Index
> Fetch the complete documentation index at: https://docs.onchainsuite.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Trial to Paid Conversion

> Turn free trials into paying customers with a nudge series timed to the trial window.

**Goal.** When someone starts a free trial, guide them to the "aha" moment and ask for the upgrade before the trial ends.

**Who it's for.** Web2 SaaS and apps with a trial or freemium plan.

**Outcome to move.** Trial-to-paid conversion rate.

## Prerequisites

* A [verified sending domain](/settings/domain-authentication) and a [secret key](/integrations/api-keys).

## Build it

<Steps>
  <Step title="Send trial and upgrade events">
    Send `trial_started` when the trial begins (put the end date in `attributes`), and `subscription_started` when they pay. The automation runs between the two and exits when they convert.

    ```bash theme={"theme":{"light":"light-plus","dark":"dark-plus"}}
    curl -X POST https://api.onchainsuite.com/api/v1/events \
      -H "Authorization: Bearer sk_live_…" \
      -H "Content-Type: application/json" \
      -d '{
        "event": "trial_started",
        "contact": { "email": "alice@example.com" },
        "attributes": { "plan": "pro", "trial_ends": "2026-11-01" }
      }'
    ```

    Other languages follow the same shape, see the [API Reference](/api-reference).
  </Step>

  <Step title="Build the conversion series">
    Trigger on `trial_started` and space a few emails across the trial:

    `trigger → send email (Get set up) → wait 2 days → send email (The feature worth trying) → wait until 2 days before trial_ends → send email (Your trial ends soon)`

    Add a [Branch](/automation/triggers-and-conditions#branches-route-entries-down-different-paths) so anyone who sends `subscription_started` drops out and gets a thank-you instead of the "ends soon" push.
  </Step>

  <Step title="Follow up after the trial ends (optional)">
    One more email a day or two after expiry, with a clear path back, catches the people who meant to upgrade and forgot.
  </Step>

  <Step title="Activate and publish.">
    Both are required.
  </Step>
</Steps>

## Test

Send `trial_started` with your own email, confirm the series fires and the "ends soon" timing is right. Send `subscription_started` and confirm it exits the series.

## Measure

* **Conversion rate** of the trial cohort.
* **Which email precedes the upgrade** (use the [campaign report](/analytics/campaign-report)) to learn what moves people.
* **Activation events** (did they reach the "aha" action) correlated with conversion.

## Variations

* **Branch on usage.** Send active and inactive trials different messages, active users get a nudge to upgrade, inactive ones get help getting started.
* **Offer at the end.** A time-boxed discount on the last day can lift conversion.


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