This n8n Workflow Processed 2,400 Invoices While I Slept 🔥
Client sends 80 invoices daily via email. Built n8n workflow that runs 24/7 processing everything automatically. Woke up to Slack notification: "2,400 invoices processed, 2,387 posted to QuickBooks, 13 flagged for review." Zero errors. Zero manual work. THE WORKFLOW (7 NODES): Gmail Trigger → monitors invoice folder Parse Document node → converts PDF to clean text Extract Structured Data node → pulls vendor, date, amount, line items using JSON schema Function Node → validates amounts, checks for duplicates Switch Node → routes based on confidence scores QuickBooks → posts approved invoices Slack → notifies on completion + flags exceptions Total build time: 3 hours Monthly processing: 2,400 invoices Accuracy: 99.4% JSON SCHEMA: { "vendor_name": "string", "invoice_date": "date", "invoice_number": "string", "total_amount": "number", "line_items": ["array"] } The workflow template pattern is here CLIENT IMPACT: Before: Bookkeeper 60 hours monthly manually entering invoices After: Reviews 13 exceptions (30 minutes monthly) Savings: $18,000 annually THE LESSON: n8n workflows run continuously. Build once, processes forever. Document automation is perfect for set-and-forget workflows. Most powerful combination: Gmail trigger + document extraction + destination API. That's 80% of document automation right there. What documents could process themselves while you sleep?