n8n Google Sheets: Auto Assign Ticket IDs by Department

Automatically assign sequential Google Sheets Ticket IDs by department (Sales, Support, Billing) in n8n

This n8n workflow reads your Google Sheets rows and auto-assigns the next available Ticket Number per Department, filling only blank values—without changing any ticket IDs you’ve already set.

What this workflow does

Designed to keep ticket tracking consistent, the workflow:

• Runs manually when you execute it in n8n.
• Fetches all rows from a specified Google Sheets worksheet.
• Groups rows by the “Department” value (Sales, Support, Billing).
• For each department, finds the highest existing Ticket Number.
• Generates the next sequential ticket IDs for rows where Ticket Number is blank, ordered by Date Submitted.
• Writes the new Ticket Number values back to the matching rows in Google Sheets.

Use cases

• When a support team logs requests into Google Sheets and you need reliable, department-based ticket numbering.
• During migration or cleanup: assign missing Ticket IDs while preserving all already-issued IDs.
• SaaS operators who track Sales, Support, and Billing separately but want a single sheet with consistent numbering.

Technical details

• Trigger: Manual Trigger
• Nodes / building blocks: Code, Sticky Note, Google Sheets
• Google Sheets setup: Use an OAuth2 credential, then select your spreadsheet and worksheet in both Google Sheets steps.
• Required columns: Department, Ticket Number, and Date Submitted.
• Update matching: Ensure the update step matches the correct row (preferably via a unique identifier column rather than Customer Name if names can repeat).
• Customization: Update the department category ranges (Sales/Support/Billing) and starting numbers in the code to match your numbering scheme.