Automated Bulk Cold Email Sender using Gmail SMTP and Google Sheets

This n8n workflow automates the process of sending personalized bulk cold emails using Gmail and a Google Sheet as the data source. It's designed to help you reach out to a large number of contacts efficiently, with built-in controls for rate limiting and preventing duplicate sends.

What it does

1. Triggers on a Schedule: The workflow starts at a predefined interval (e.g., daily, hourly) to check for new emails to send.
2. Reads Data from Google Sheets: It connects to a specified Google Sheet to retrieve a list of recipients and email content.
3. Filters Sent Emails: It checks the Google Sheet to identify which emails have already been sent, preventing duplicates.
4. Limits Batch Size: Processes a defined number of emails in each run to manage sending limits and avoid overwhelming recipients.
5. Loops Through Recipients: Iterates over each unsent recipient from the Google Sheet.
6. Sends Emails via Gmail: For each recipient, it composes and sends a personalized email using your Gmail account.
7. Waits Between Emails: Introduces a delay between sending individual emails to mimic human behavior and comply with email provider sending limits.
8. Updates Google Sheet: Marks the emails as "Sent" in the Google Sheet after successful delivery, along with the timestamp.

Prerequisites/Requirements

• n8n Instance: A running n8n instance (self-hosted or cloud).
• Google Account: A Google account with access to Google Sheets and Gmail.
• Google Sheets Credential: An n8n credential configured for Google Sheets (OAuth2 recommended).
• Gmail Credential: An n8n credential configured for Gmail (OAuth2 recommended).
• Google Sheet: A Google Sheet containing your cold email recipient data. This sheet should ideally have columns for:
  • Recipient Email Address
  • Recipient Name (for personalization)
  • Email Subject
  • Email Body
  • A column to mark if the email has been sent (e.g., "Sent Status")
  • A column to record the sent timestamp (e.g., "Sent At")

Setup/Usage

1. Import the Workflow:
   • Download the provided JSON file.
   • In your n8n instance, go to "Workflows" and click "New".
   • Click the "Import from JSON" button and paste the workflow JSON or upload the file.
2. Configure Credentials:
   • Locate the "Google Sheets" and "Gmail" nodes.
   • Click on each node and select or create new Google OAuth2 credentials for your Google account. Ensure these credentials have the necessary permissions for Google Sheets and Gmail.
3. Configure Google Sheets Node:
   • In the "Google Sheets" node, specify the Spreadsheet ID and Sheet Name where your recipient data is located.
   • Adjust the "Operation" and "Options" as needed to read and update your specific sheet structure.
4. Configure "If" Node:
   • The "If" node is crucial for checking if an email has already been sent. Configure its condition to check the "Sent Status" column in your Google Sheet. For example, {{ $json.SentStatus === 'Sent' }} would route already sent emails to the "False" branch.
5. Configure "Loop Over Items" Node:
   • Adjust the "Batch Size" and "Batch Interval" to control the number of emails sent per run and the delay between batches.
6. Configure "Send Email" (Gmail) Node:
   • Set the Recipient Email Address using an expression like {{ $json.email_address }} (assuming email_address is a column in your sheet).
   • Set the Subject and Body of the email, using expressions to pull data from your Google Sheet for personalization (e.g., {{ $json.subject }}, Hello {{ $json.first_name }}, {{ $json.email_body }}).
   • Ensure your From Email Address is correctly configured.
7. Configure "Wait" Node:
   • Adjust the "Delay" in the "Wait" node to control the pause between sending individual emails. This helps avoid hitting rate limits.
8. Configure "Update Google Sheet" Node (after sending):
   • After the "Send Email" node, add another "Google Sheets" node to update the "Sent Status" and "Sent At" columns for the row that was just processed.
   • Use expressions to set the "Sent Status" to "Sent" and "Sent At" to {{ new Date().toISOString() }}.
   • Ensure you correctly identify the row to update (e.g., using a unique ID from your sheet).
9. Activate the Workflow:
   • Once configured, activate the workflow by toggling the "Active" switch in the top right corner of the n8n editor.
   • The workflow will now run automatically based on the schedule defined in the "Schedule Trigger" node.

Important Considerations:

• Gmail Sending Limits: Be aware of Gmail's daily sending limits. This workflow includes a "Wait" node to help manage this, but excessive sending can still lead to temporary blocks.
• Personalization: Leverage the data from your Google Sheet to personalize emails for better engagement.
• Error Handling: For production use, consider adding error handling (e.g., using the "On Error" workflow setting or additional nodes) to log failed sends or retry them.
• Unsubscribe Link: For compliance and good practice, always include an unsubscribe link in your cold emails. This workflow does not automatically add one, so ensure your email body content includes it.