We have automated the cleaning of cold email campaigns for an outbound agency's with 70 active clients, removing the need to hire additional staff

Introduction

Our client is a cold email service provider (outbound agency) that helps local businesses find new leads. They send cold emails on behalf of these local businesses to generate more customers. They have over 70 active clients and growing.

The client heavily relies on SmartLead.ai to send these emails. However, to get better results, they needed a way to automatically clean and manage their cold email campaigns. That’s where our automation with n8n.io comes in.

The Goal

We built an automation that:

1. Checks campaigns for high bounce rates in SmartLead.
2. Re-verifies leads through an email validation service (BounceBan).
3. Removes invalid leads and re-imports catch-all leads under specific conditions.
4. Keeps track of each cleaning using Google Sheets, Slack messages, and Airtable comments.

The main reason for doing this is to improve email deliverability and make sure the client doesn’t waste resources on invalid or risky leads.

Tools We Use

1. n8n.io for the entire workflow automation.
2. airtable.com to store client lists and record all operations (including a form to submit campaign details).
3. smartlead.ai to send cold emails and manage campaigns.
4. bounceban.com to verify email addresses (valid, invalid, catch-all, risky).
5. Google Sheets to record removed leads and share with our client’s sales development reps (SDRs).
6. Slack for notifications and quick communication.

How the Process Works

1. Submitting the Form in Airtable

Our client fills out an Airtable form whenever they spot a campaign with a high bounce rate or want to clean a list. The form asks for:

• Campaign link (from SmartLead).
• Client name (chosen from existing records in Airtable).
• Two options to include catch-all emails or risky emails.

After submitting, this triggers our first automation in n8n (called Automation Part 1).

2. Automation Part 1 (Initial Cleanup)

1. Login to SmartLead We connect to the backend API (instead of the official API because of limitations) to get an authentication token.
2. Pause the Campaign We pause the campaign to make sure no emails get sent while we are cleaning leads.
3. Get Campaign Details We fetch information about the campaign to see how many leads are inside and which ones have not yet received an email.
4. Get All Non-Contacted Leads We only want to verify leads that haven’t been emailed yet.
5. Send Leads to BounceBan for Verification We send these leads to BounceBan, which checks if an email is valid, invalid, catch-all, or risky.

Once BounceBan finishes the verification, it triggers the second automation (called Automation Part 2).

3. Automation Part 2 (Removing and Re-Importing Leads)

1. Gather Verification Results

Automation Part 2 receives a CSV from BounceBan with the verification status for each email.

2. Decide Which Leads to Remove or Re-Import

This depends on what the user chose in the Airtable form (include catch-all, include risky). Here’s the breakdown:

- If “include_catch_all” = Yes

- Status = Undeliverable: remove from campaign.

- Status = Risky: remove from campaign.

- Status = Deliverable & Accept All = false: leave it alone (it’s a valid email).

- Status = Deliverable & Accept All = true (catch-all): remove from campaign, then re-import.

- If “include_catch_all” & “include_risky” = Yes

- Status = Undeliverable: remove from campaign.

- Status = Risky: remove and re-import.

- Status = Deliverable & Accept All = false: leave it alone.

- Status = Deliverable & Accept All = true: remove and re-import.

- If “include_catch_all” is NOT “Yes”

- Status = Undeliverable: remove from campaign.

- Status = Risky: remove from campaign.

- Status = Deliverable & Accept All = false: leave it alone.

- Status = Deliverable & Accept All = true: remove from campaign

The reason we re-import catch-all (and sometimes risky) emails is to send them after valid emails. SmartLead sends emails to the newest leads last, so valid emails get contacted first, giving the best chance for high deliverability.

3. Create a Google Sheet of Removed Leads

We create a Google Sheet with the client’s name and today’s date. Then, we move this sheet into the client’s folder. We list all removed leads in this sheet, so the client’s SDR team (sales) can reach out via cold-call or social media as we can't send cold emails to those leads.

This way no leads get wasted and all of them get contacted.

4. Send Slack Message and Airtable Comment

We post a summary of what happened, including how many emails were removed or re-imported, what choices were made in the form, and the final status. This log is also added as a comment in Airtable and also slack message, so we have a full history for each client.

5. Resume the Campaign

Finally, we un-pause (resume) the campaign so that it can keep sending cold emails to the cleaned list.

Why This Automation Matters

• Better Email Deliverability: By removing invalid and risky emails, the client keeps bounce rates low. This improves sender reputation and helps more emails land in the inbox.
• Effective Organization: Everything is controlled by an Airtable form. The client just fills out a quick form and the rest is automated.
• Saves Time: Instead of manually downloading leads, verifying, and re-importing them, our n8n workflows handle everything.
• Full Tracking and Logs: Every cleaning session is recorded, with Slack messages, Airtable comments, and a Google Sheet copy, so there’s always a clear history.

Conclusion

With this n8n.io automation, our client can keep their cold email campaigns as clean as possible. They no longer need to worry about high bounce rates or unorganized lead lists. The process happens behind the scenes, and they only need to fill out one simple form in Airtable. This helps them focus on what matters most—bringing new leads to local businesses and growing their revenue.

Service we provide: We will automate and systemize your business operations, enabling your existing team to handle 20 times more work without hiring additional staff - If you're interested, email me at [email protected]

Visit our website: Twomarkup.com to learn more.