WooCommerce Inventory Reorder Automation with n8n, Gmail & Slack Alerts

Automatically track product sales and inventory levels in WooCommerce and trigger reorder notifications when stock runs low or sales spike.

This n8n workflow runs daily, analyzes all WooCommerce orders to calculate SKU-wise sales, compares them with current product stock, calculates an optimal reorder quantity and sends automated alerts via Email (Gmail) and Slack when a product meets reorder conditions.

Quick Implementation Steps (Get Started Fast)

1. Import the workflow JSON into your n8n instance.
2. Connect WooCommerce, Gmail and Slack credentials.
3. Set the Schedule Trigger to run daily.
4. Update email recipients and Slack channel.
5. Activate the workflow.

What It Does

This workflow automates inventory monitoring and reorder decision-making for WooCommerce stores. On a daily schedule, it fetches all orders from WooCommerce and calculates how many units of each SKU were sold. This gives you a clear picture of recent sales velocity without manual reporting.

The workflow then retrieves live product inventory data from WooCommerce, including current stock levels and low-stock thresholds. Sales data and product data are merged using SKU matching and evaluated using logical conditions to determine whether a product should be reordered.

When a product meets the reorder criteria, the workflow calculates an optimal reorder quantity using average daily sales, supplier lead time and safety stock logic. It then automatically notifies the purchasing team via email and Slack, ensuring no critical stock replenishment is missed.

Who’s It For

This workflow is ideal for:

• WooCommerce store owners
• Inventory and supply chain managers
• E-commerce operations teams
• Businesses looking to reduce stockouts
• Teams that want proactive, automated purchase alerts

Requirements to Use This Workflow

To use this workflow, you will need:

• An active n8n instance
• A WooCommerce store with:
  • Products using SKUs
  • Stock management enabled
• WooCommerce API credentials with access to:
  • Orders
  • Products
• A Gmail account connected to n8n (OAuth2)
• A Slack workspace with bot permissions
• Basic understanding of n8n nodes and credentials

How It Works & How To Set Up

Step-by-Step Workflow Logic

1. Schedule Trigger (Daily)
   • The workflow runs automatically once per day.
2. Fetch All WooCommerce Orders
   • Retrieves all available orders from WooCommerce.
   • No status or date filtering is applied.
3. Calculate Sales per SKU
   • A JavaScript Code node loops through order line items.
   • Quantities sold are aggregated per SKU.
4. Fetch All WooCommerce Products
   • Retrieves product inventory data including:
     • Stock quantity
     • Low stock threshold
     • Product name
5. Merge Sales & Product Data
   • Sales data and product inventory data are merged using SKU matching.
6. Reorder Eligibility Filter
   • A product qualifies if either condition is met:
     • Current stock ≤ low-stock threshold
     • OR recent sales quantity ≥ 1.5× low-stock threshold
7. Reorder Quantity Calculation
   • Uses:
     • Average daily sales
     • Fixed lead time (7 days)
     • Safety stock (5 units)
   • Calculates recommended reorder quantity.
8. Email Notification
   • Sends a formatted HTML email with reorder details.
9. Slack Notification
   • Sends a real-time alert to a specified Slack channel.

How To Customize Nodes

You can easily adapt this workflow to your business needs:

• Schedule Trigger
  • Change execution frequency (daily, weekly, etc.).
• Sales Calculation Code
  • Modify logic to:
    • Ignore certain SKUs
    • Add time-based filtering
    • Apply weighted averages
• Filter Conditions
  • Adjust reorder rules:
    • Change sales multiplier
    • Use AND logic instead of OR
• Reorder Formula
  • Update lead time or safety stock values.
  • Integrate supplier-specific rules.
• Email & Slack Nodes
  • Replace recipients and channels.
  • Customize message formatting or branding.

Add-ons (Extend the Workflow)

You can enhance this workflow with:

• Automatic purchase order creation in ERP systems
• Google Sheets logging for reorder history
• Vendor-specific reorder logic
• Forecast-based inventory planning
• Approval workflows before notifications
• Webhook integration with procurement tools

Use Case Examples

Primary use cases include:

1. Preventing stockouts in fast-moving WooCommerce stores
2. Automating daily inventory monitoring
3. Supporting purchasing teams with data-driven reorder alerts
4. Replacing manual stock checks and spreadsheets
5. Improving response time to sudden sales spikes

There are many more variations of this workflow that can be adapted to different industries and store sizes.

Troubleshooting Guide

Need Help?

Need assistance setting up this workflow or customizing it for your business?

Our n8n workflow development team at WeblineIndia specializes in building advanced n8n automations, WooCommerce integrations and end-to-end business process workflows.

Whether you need enhancements, add-ons or a completely custom automation solution, our experts are here to help you streamline operations and scale efficiently.

Contact WeblineIndia to get started with smarter automation today.