Reminders.

A reminder is a follow-up push notification that Samply sends automatically when it has not detected a survey completion for the original send. Reminders are optional and configured per schedule. They fire at a fixed offset after the original notification — unless the participant completes the survey first, in which case Samply cancels all pending reminders for that send automatically.

How reminders work

When Samply dispatches an original notification, it immediately schedules any configured reminder rows in the queue. Each reminder row is a separate pending queue entry with Reminder: yes. The reminder inherits the same survey URL (including all substituted placeholder values) as the original send — participants who tap the reminder link land in the same survey session.

Reminders are cancelled in two ways:

1. Samply receives a completion event for the original send (via redirect or POST request — see below). It immediately cancels all pending reminders that share the same internal send ID.
2. You manually delete the schedule or cancel the rows from the queue.

Without a completion event, every send gets a reminder regardless of whether the participant actually completed the survey.

Configuring reminders in the schedule form

Step 9 of the schedule form is the reminder section. Toggle Send reminders to reveal the reminder planner. For each reminder you want to send, fill in:

Reminder title

The bold first line of the reminder push notification on the participant device.

Reminder message

The notification body — the second line visible in the system tray.

Sent after

The delay from the original notification: days + hours + minutes. A reminder set to 0 days, 1 hour, 0 minutes fires one hour after the original send. All three fields default to 0 — set at least one to a non-zero value.

Click Add new reminder to add a second reminder at a different offset. You can chain as many reminders as needed — for example, a first reminder at 1 hour and a second at 4 hours. All reminders are cancelled as soon as a completion event arrives, regardless of which have already fired.

Registering a completion event

Samply cannot know on its own when a participant finishes a survey. Your survey tool must signal completion by calling the Samply completion endpoint. There are two ways to do this.

The exact URLs for your study — with the correct slug already filled in — are shown in the Settings tab of your study dashboard, under Reminders — completion URL. You can copy them directly from there.

Option 1 — redirect (Qualtrics, LimeSurvey, most survey tools)

At the end of your survey, redirect the participant to the Samply completion URL. Samply marks the send as completed and cancels pending reminders, then shows the participant a confirmation page.

The redirect URL follows this pattern — replace your-study-slug with your study URL slug and use the %MESSAGE_ID%placeholder so each participant's completion is recorded against their specific send:

In Qualtrics, set this as the survey end-of-survey redirect URL. In LimeSurvey, set it as the "End URL" on the survey settings panel. The survey tool substitutes %MESSAGE_ID% with the actual message ID it received via the URL parameter you passed in the notification link (see URL placeholders).

Option 2 — POST request (REDCap, custom integrations)

Send an HTTP POST to the same endpoint. This is suited for survey tools that support end-of-survey webhooks, or for custom code running server-side.

A 200 response confirms the completion was recorded and reminders were cancelled. A 400 response means Samply could not find a matching result record for that message ID — check that %MESSAGE_ID% was correctly substituted and passed through.

Why MESSAGE_ID is required

Samply uses %MESSAGE_ID% to link a completion event to the exact notification send that triggered the survey. Without it, Samply cannot identify which pending reminders to cancel. The flow is:

1. You put %MESSAGE_ID% in the notification Web Link as a query parameter — for example, ?messageid=%MESSAGE_ID%.
2. Samply substitutes the token with a unique 15-character ID at send time. The participant opens the survey URL with that ID already in it.
3. Your survey tool reads the messageid parameter and passes it to the end-of-survey redirect or webhook.
4. Samply receives the completion call with the message ID, cancels reminders, and marks the result record as completed.

If you use reminders, always include %MESSAGE_ID% in your notification URL and verify that your survey tool forwards it to the completion endpoint.

Qualtrics setup walkthrough

1. In the notification Web Link, add ?messageid=%MESSAGE_ID% (plus any other placeholders you need).
2. In your Qualtrics survey flow, add an Embedded Data element before the first block and create a field named messageid. Qualtrics captures query string parameters automatically.
3. In Survey Options → Survey Termination, set the redirect URL to:

Qualtrics substitutes {e://Field/messageid} with the captured value, so participants are redirected to the correct completion URL.

Things to watch out for

Reminders fire if no completion event arrives

If the redirect or POST never reaches Samply — because the participant abandoned the survey mid-way, because the survey tool was misconfigured, or because the completion URL had a typo — the reminder will fire as scheduled. Test the full flow with a test participant before going live.

Reminders inherit the original substituted URL

The survey URL embedded in reminder notifications is the already-substituted URL from the original send — not a fresh substitution. The same message ID, batch number, and timestamps apply. This is intentional: the reminder should reopen the same survey session. If your survey tool creates a new response for each link open, ensure your logic handles this.

Reminder rows count toward the queue limit

Each reminder row is a separate pending entry in the queue and counts toward the 50,000-row limit per study. A schedule with 100 participants and 2 reminders per send generates 3 rows per send, not 1.