Automate Task Deadline Reminders with Google Sheets and Gmail (Today/3-Day/7-Day)

Task Deadline Reminder Workflow (Today / 3-Day / 7-Day) Task deadline management manually is inefficient and leads to missed deadlines—especially when teams rely on spreadsheets and individual reminders.
This workflow automates the entire follow-up process by reading a centralized task sheet in Google Sheets every morning, checking the deadline for each task, and sending automatic email notifications to the responsible person based on urgency.
Tasks due today, within three days, or within one week are identified and routed to customized Gmail notifications, ensuring that every team member is aware of upcoming deadlines without manual checking.

Who’s it for This workflow is ideal for teams and organizations that manage multiple tasks across departments and need a reliable way to stay on top of deadlines. It is especially useful for:

Project managers coordinating many deadlines
Back-office teams monitoring routine operational tasks
Organizations with distributed members
Anyone who relies on spreadsheets but needs automated follow-up

By integrating Google Sheets, n8n, and Gmail, you gain a proactive notification system that keeps everyone aligned and reduces the risk of forgotten tasks.

How it works

1. Daily trigger
   The workflow runs every morning at 9:00 using a Schedule Trigger.

2. Load task list from Google Sheets
   The workflow retrieves all rows from the designated spreadsheet, including task name, deadline, responsible person, and email address.

3. Process tasks individually
   A loop node evaluates each task one by one.

4. Evaluate deadline conditions
   Due today:** Deadline matches today’s date
   Due within 3 days:** Deadline falls between today and three days ahead
   Due within 7 days:** Deadline falls between today and one week ahead

5. Send notifications
   Depending on urgency:
   “本日が締め切りです” for tasks due today
   “タスク期限が三日前となりました” for tasks due within 3 days
   “タスクの期限が一週間以内です” for tasks due within 7 days

Each email is automatically sent to the responsible person based on the “メールアドレス” field in the sheet.

6. Complete processing
   The loop continues until all task rows have been checked.

How to set up Import the workflow into your n8n instance
Authenticate Google Sheets and select the task spreadsheet
Authenticate Gmail as the sender account
Confirm required columns: タスク, 期限, 担当, メールアドレス
Adjust time, message text, or conditions based on your internal rules

Requirements Active n8n instance
Google Sheets access with permission to read the task list
Gmail OAuth connection for email sending
Spreadsheet with at least: task name, deadline, responsible person, email address

How to customize You can expand and refine this workflow to match your company’s processes:

Add Slack, Chatwork, or LINE notifications
Add overdue task detection
Add task priority sorting (High / Medium / Low)
Log notifications back into the spreadsheet
Send daily summary reports to managers

This workflow provides a flexible foundation for building a complete automated task governance system.