Automated invoice payment reminders with Google Sheets and Gmail

How It Works ⚙️

This workflow systematically ensures you never miss sending an invoice reminder:

1. Daily Schedule Trigger: ⏰ The workflow starts automatically at a set time each day (e.g., every morning). This ensures continuous monitoring of your invoice statuses. 2. Read Invoice Data (Google Sheets): 📊 The workflow connects to your specified Google Sheet to retrieve a list of all your invoices and their details. Ensure your sheet has required columns like InvoiceID, ClientName, ClientEmail, Amount, DueDate, and Status. 3. Filter & Prepare Reminders (Function): 🧹 This is the core logic. It processes each invoice row: Compares the DueDate with the current date. Identifies invoices that are due soon (e.g., within 3 days) or are already overdue (e.g., up to 7 days past due). Skips invoices marked as 'Paid'. Prepares a custom subject line and email body for each relevant reminder. 4. If Invoices to Remind?: 🚦 This node acts as a gate. If the previous step found any invoices needing reminders, the workflow proceeds. If not, it stops gracefully. 5. Send Invoice Reminder (Gmail): 📧 For each filtered invoice, this node sends a personalized email reminder to the client. The email uses the dynamic subject and body prepared in the 'Filter & Prepare Reminders' step.

How to Set Up 🛠️

Follow these steps carefully to get your "Automated Invoice Reminder" workflow up and running:

1. Import Workflow JSON: Open your n8n instance. Click on 'Workflows' in the left sidebar. Click the '+' button or 'New' to create a new workflow. Click the '...' (More Options) icon in the top right. Select 'Import from JSON' and paste the entire JSON code provided in the previous response for this workflow.

2. Configure Daily Schedule Trigger: Locate the 'Daily Schedule Trigger' node (1. Daily Schedule Trigger). Adjust 'interval', 'value', and 'timezone' to your preferred daily reminder time (e.g., every 24 hours at 9 AM in your local timezone).

3. Configure Read Invoice Data (Google Sheets): Locate the 'Read Invoice Data (Google Sheets)' node (2. Read Invoice Data). Credentials: Select your existing Google Sheets OAuth2 credential or click 'Create New' to set one up. Replace YOURGOOGLESHEETSCREDENTIALID with the actual ID or name of your credential from your n8n credentials. Sheet ID: Replace YOURGOOGLESHEETID with the actual ID of your Google Sheet where invoice data is stored. Range: Ensure the 'range' (e.g., Invoices!A:F) correctly covers all your invoice data. Crucially, ensure your Google Sheet has columns with exact names: InvoiceID, ClientName, ClientEmail, Amount, DueDate (in a parsable date format like YYYY-MM-DD), and Status (e.g., 'Pending', 'Paid').