Send WhatsApp payment reminders automatically with MoltFlow

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1. Workflow Overview

How it works This workflow automates WhatsApp payment reminders using the MoltFlow API. No more chasing clients manually — reminders go out every morning at 9 AM with personalized messages. 1. A sc...

Best for

Invoice Processing automation workflows
intermediate n8n builders looking for reusable templates

Tools used

n8n-nodes-base.stickynote, n8n-nodes-base.scheduletrigger, n8n-nodes-base.code, n8n-nodes-base.httprequest, n8n-nodes-base.if

Source and attribution

This workflow is cataloged by N8N Workflows and links back to its original n8n.io source page by Alex Pekler.

Original n8n.io source

1.1 Workflow description

Title: Send WhatsApp payment reminders automatically with MoltFlow
Workflow name: Send WhatsApp payment reminders automatically with MoltFlow

How it works

This workflow automates WhatsApp payment reminders using the MoltFlow API. No more chasing clients manually — reminders go out every morning at 9 AM with personalized messages.

A schedule trigger fires daily at 9 AM
A code node builds your contact list with names, amounts, and due dates
Each contact receives a personalized WhatsApp reminder via MoltFlow
Results are logged — you can see which messages succeeded and which failed

Set up steps

Setup takes about 3 minutes:

Create a free MoltFlow account and connect your WhatsApp by scanning the QR code
Generate an API key from Sessions → API Keys tab (select the "Messaging" scope preset)
In n8n, add a Header Auth credential — set header name to X-API-Key and paste your MoltFlow API key as the value
Open the Prepare Contacts code node and replace YOUR_SESSION_ID with your MoltFlow session ID
Edit the contacts array with your actual client data (phone, name, amount, due date)
Customize the message template if needed
Activate the workflow — reminders will go out every morning

Prerequisites

A MoltFlow account (free tier available)
A connected WhatsApp session
MoltFlow API key with messages:send scope

1.2 Logical Blocks

This catalog entry is organized from the workflow JSON. The node-level section below shows the executable blocks available for review before importing the template.

2. Block-by-Block Analysis

Block 1 - Sticky Note

Type / Role: n8n-nodes-base.stickyNote - stickyNote
Config choices: Version 1

Block 2 - Sticky Note1

Type / Role: n8n-nodes-base.stickyNote - stickyNote
Config choices: Version 1

Block 3 - Daily 9 AM Trigger

Type / Role: n8n-nodes-base.scheduleTrigger - scheduleTrigger
Config choices: Version 1.2

Block 4 - Prepare Contacts

Type / Role: n8n-nodes-base.code - code
Config choices: Version 2

Block 5 - Send WhatsApp Reminder

Type / Role: n8n-nodes-base.httpRequest - httpRequest
Config choices: Version 4.2

Block 6 - Message Sent?

Type / Role: n8n-nodes-base.if - if
Config choices: Version 2

Block 7 - Log Success

Type / Role: n8n-nodes-base.code - code
Config choices: Version 2

Block 8 - Log Failure

Type / Role: n8n-nodes-base.code - code
Config choices: Version 2

3. Summary Table

Workflow	Send WhatsApp payment reminders automatically with MoltFlow
Complexity	intermediate
Nodes	8
Categories	Invoice Processing
Author	Alex Pekler
Published	18 Feb 2026

4. Reproducing the Workflow from Scratch

1. Download the workflow JSON

Use the JSON export at /data/workflows/13475/13475.json as the source template for this automation.
2. Import the template into n8n

Open n8n, import the downloaded JSON, and review each node before activating the workflow.
3. Configure credentials and variables

Replace placeholder credentials, API keys, webhook URLs, account IDs, and environment-specific values with your own settings.
4. Test with sample data

Run the workflow manually or in a staging workspace, inspect node output, and confirm downstream systems receive the expected data.
5. Activate and monitor

Enable the workflow only after testing, then monitor executions, errors, and rate limits during the first production runs.

5. General Notes & Resources

Review imported nodes carefully before activation. This catalog entry is intended to help you inspect the workflow structure, understand required services, and find related templates faster.

Node names, credentials, schedules, webhook paths, and external service limits may need adjustment for your workspace.

Download workflow JSON Original n8n.io source Invoice Processing workflows

Frequently asked questions

What does Send WhatsApp payment reminders automatically with MoltFlow do?

What do I need before importing this workflow?

Review the workflow JSON, configure any required credentials in n8n, and test the automation in a safe workspace before using it in production.

Can I customize this workflow?

Yes. Use the block-by-block analysis and the downloadable JSON to inspect each node, then adjust credentials, prompts, schedules, filters, or destinations for your Invoice Processing use case.

Alex Pekler

9 workflows

Nodes

n8n-nodes-base.stickynote n8n-nodes-base.scheduletrigger n8n-nodes-base.code n8n-nodes-base.httprequest n8n-nodes-base.if

Complexity

intermediate

Published 18 Feb 2026

Likes 0

View on n8n.io Download Workflow

Install path: /data/workflows/13475/13475.json

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Send WhatsApp payment reminders automatically with MoltFlow

Workflow preview

1. Workflow Overview

Best for

Tools used

Source and attribution

1.1 Workflow description

How it works

Set up steps

Prerequisites

1.2 Logical Blocks

2. Block-by-Block Analysis

Block 1 - Sticky Note

Block 2 - Sticky Note1

Block 3 - Daily 9 AM Trigger

Block 4 - Prepare Contacts

Block 5 - Send WhatsApp Reminder

Block 6 - Message Sent?

Block 7 - Log Success

Block 8 - Log Failure

3. Summary Table

4. Reproducing the Workflow from Scratch

1. Download the workflow JSON

2. Import the template into n8n

3. Configure credentials and variables

4. Test with sample data

5. Activate and monitor

5. General Notes & Resources

Frequently asked questions