Automated invoice follow-ups with smart response tones via Google Sheets & email
Needs changesNeeds changes. This template uses 2 thing(s) that n8n 3.0 removes: Cron, Function (legacy). 2 breaking item(s) found. Static check, last run 2026-10-19.
What this workflow does
This workflow has 6 nodes and runs on a schedule (legacy Cron node). Along the way it connects Google Sheets.
How it runs
Trigger: On a schedule (legacy Cron node).
- Load Invoices (Google Sheets): lookup
- Filter Overdue Invoices (Function): runs custom JavaScript (legacy Function node)
- Calculate DPD (Function): runs custom JavaScript (legacy Function node)
- Generate Message (Function): runs custom JavaScript (legacy Function node)
- Send Email: sends an email over SMTP
Services it uses
Before you upgrade to n8n 3.0
2 things in this workflow are removed in n8n 3.0. Fix them before you upgrade:
- Cron in Daily Trigger: replace with Schedule Trigger.
- Function (legacy) in Filter Overdue Invoices, Calculate DPD, Generate Message: replace with Code node, mode 'Run Once for All Items'.
Rather not rewrite it? Many of these flows can be rebuilt in Make (free plan).
| Removed in 3.0 | Replace with |
|---|---|
| Cron Daily Trigger | Schedule Trigger |
| Function (legacy) Filter Overdue Invoices, Calculate DPD, Generate Message | Code node, mode 'Run Once for All Items' |
Nodes used (4)
- Cron
n8n-nodes-base.cron - Google Sheets
n8n-nodes-base.googleSheets - Function
n8n-nodes-base.function - Send Email
n8n-nodes-base.emailSend
From the author
🔍 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…