Automated invoice follow-ups with smart response tones via Google Sheets & email

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Important notice

This workflow is provided as-is. Please review and test before using in production.

1. Workflow Overview

How It Works This AI Agent checks your invoice database (Google Sheets) daily and looks for unpaid invoices that are past their due date. It calculates how many days each invoice is overdue (Day...

Best for

Invoice Processing automation workflows
Multimodal AI automation workflows
intermediate n8n builders looking for reusable templates

Tools used

n8n-nodes-base.cron, n8n-nodes-base.googlesheets, n8n-nodes-base.function, n8n-nodes-base.emailsend, n8n-nodes-base.stickynote

Source and attribution

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

Original n8n.io source

1.1 Workflow description

Title: Automated invoice follow-ups with smart response tones via Google Sheets & email
Workflow name: Automated invoice follow-ups with smart response tones via Google Sheets & email

🔍 How It Works This AI Agent checks your invoice database (Google Sheets) daily and looks for unpaid invoices that are past their due date. It calculates how many days each invoice is overdue (Days Past Due / DPD), then automatically crafts a follow-up message with an appropriate tone:

1–7 days overdue: Friendly reminder
8–14 days overdue: Slightly firm nudge
15+ days overdue: Final warning tone

After generating the message, it sends the follow-up via email to the client and logs the interaction. You can extend this to send WhatsApp messages, Slack alerts, or update a CRM.

⚙️ Set Up Steps

Connect Google Sheets : Replace YOUR_SHEET_ID in the workflow with the actual Sheet ID
Make sure your sheet has these columns: client_name, email, invoice_number, due_date, status
Adjust Cron Trigger
By default, it runs daily — you can change the frequency in the “Daily Trigger” node.
Configure Email Node
Set your email sender (Gmail, SMTP, or Mailgun) in the “Send Email” node.
Customize Messages (Optional)
Modify tone and content in the “Generate Message” node based on your brand style.
Run & Monitor
Activate the workflow
Monitor activity in Google Sheets or add a logging step (Notion, Slack, etc.)

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 - Daily Trigger

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

Block 2 - Load Invoices

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

Block 3 - Filter Overdue Invoices

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

Block 4 - Calculate DPD

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

Block 5 - Generate Message

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

Block 6 - Send Email

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

Block 7 - Sticky Note

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

Block 8 - Sticky Note1

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

3. Summary Table

Workflow	Automated invoice follow-ups with smart response tones via Google Sheets & email
Complexity	intermediate
Nodes	8
Categories	Invoice Processing, Multimodal AI
Author	Marth
Published	20 Jul 2025

4. Reproducing the Workflow from Scratch

1. Download the workflow JSON

Use the JSON export at /data/workflows/6192/6192.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 Multimodal AI workflows

Frequently asked questions

What does Automated invoice follow-ups with smart response tones via Google Sheets & email do?

How It Works This AI Agent checks your invoice database (Google Sheets) daily and looks for unpaid invoices that are past their due date. It calculates how many days each invoice is overdue (Day...

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, Multimodal AI use case.

Marth

52 workflows

Nodes

n8n-nodes-base.cron n8n-nodes-base.googlesheets n8n-nodes-base.function n8n-nodes-base.emailsend n8n-nodes-base.stickynote

Complexity

intermediate

Published 20 Jul 2025

Likes 0

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Install path: /data/workflows/6192/6192.json

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Automated invoice follow-ups with smart response tones via Google Sheets & email

Workflow preview

Important notice

1. Workflow Overview

Best for

Tools used

Source and attribution

1.1 Workflow description

1.2 Logical Blocks

2. Block-by-Block Analysis

Block 1 - Daily Trigger

Block 2 - Load Invoices

Block 3 - Filter Overdue Invoices

Block 4 - Calculate DPD

Block 5 - Generate Message

Block 6 - Send Email

Block 7 - Sticky Note

Block 8 - Sticky Note1

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