Independent Portfolio Project · n8n
AI-Powered Invoice Processing & Approval
An end-to-end invoice processing workflow integrating Gmail, AI-powered data extraction, Google Drive, and Google Sheets.
Project Overview
- Automated invoice intake and data extraction
- Invoice validation
- Approval and rejection routing
- Escalation handling
- Document archiving
- Final email notifications
The Business Problem
Invoices that arrive by email usually need someone to open each attachment, retype the details, check them, chase approvers, and file the document — slow, repetitive work that is easy to get wrong.
The Solution
The n8n workflow picks up invoices from Gmail, uses AI to extract the key fields, validates them, routes each invoice for approval or rejection with escalation handling, archives the document in Google Drive, and tracks status centrally in Google Sheets.
Workflow Breakdown
- 01
Intake
Incoming invoice emails are captured from Gmail.
- 02
AI extraction
AI-powered extraction reads the invoice data from the attachment.
- 03
Validation
Extracted values are checked before moving forward.
- 04
Approval routing
Invoices are routed to approve or reject, with escalation handling.
- 05
Archive & track
Documents are archived in Google Drive with centralized tracking in Google Sheets.
- 06
Notify
Final email notifications close the loop.
Tools & Integrations
Video Walkthrough
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Workflow Gallery
Explore the actual workflow, sample invoice, and tracking records used in this automation project.
Key Takeaways
- Connecting email, AI, file storage, and spreadsheets in one flow
- Designing approval, rejection, and escalation branches
- Building a document archive with approval visibility