Automatic Invoice Generation and Email with Airtable and CustomJS PDF Generator

Description

> ⚠️ Notice:
> This workflow uses the CustomJS Invoice Generator node from customjs.space, which requires a self-hosted n8n instance and a CustomJS API key.

Google Spreadsheet → Invoice Generation → Email Workflow

This workflow demonstrates how to:

Pull invoices ready to be sent from Airtable.
Retrieve client details and invoice items from Airtable.
Generate a professional invoice PDF using CustomJS Invoice Generator.
Send the completed invoice via email to the client.
Update the invoice status in Airtable automatically.


Public Airtable Example

Workflow Overview

1. Trigger Workflow
Node:** When clicking ‘Execute workflow’ (Manual Trigger)
Starts the workflow when executed manually in n8n.

2. Get Ready Invoices
Node:** Get Ready Invoices (Airtable)
Retrieves all invoices from Airtable where Status = 'Ready'.

3. Loop Over Items
Node:** Loop Over Items (Split In Batches)
Processes each invoice individually.

4. Get Clients
Node:** Get Clients (Airtable)
Fetches client details for the current invoice:
Name
Address
Tax ID

5. Get Invoice Items
Node:** Get Invoice Items (Airtable)
Retrieves all items associated with the invoice and passes them for aggregation.

6. Map Fields
Node:** Map Fields (Set)
Maps the invoice items into a structured format for the invoice generator:
Description
Quantity / Hours
Unit Price
Invoice ID

7. Aggregate
Node:** Aggregate
Aggregates all invoice items into a single JSON array for the invoice.

8. Set Company Details
Node:** Set Company Details (Set)
Defines issuer and payment information:
Company Name
Address
Tax ID
Email & Phone
Bank Details

9. Generate Invoice
Node:** Generate Invoice (CustomJS Invoice Generator)
Generates a PDF invoice using all collected data:
Issuer / Company information
Recipient / Client information
Invoice items
Billing information (Invoice number, date, currency, tax, notes)

10. Send Email With Attachment
Node:** Send Email With Attachment (Email Send)
Sends the generated invoice PDF to the client:
From: {{ $json.InvoiceEmail }}
To: [email protected]
Subject: Your Invoice for Last Month
Body Text:

Hello,

Please find attached your invoice for the last month. Thank you very much for your cooperation.

Best regards,
Henrik

Uses SMTP credentials for sending emails.

11. Update Record
Node:** Update record (Airtable)
Marks the invoice as Sent in Airtable.

Requirements

Self-hosted n8n instance
CustomJS API key
SMTP credentials
Airtable API key and base access