BlogMarketing Automation Case Study: Hyper-Targeted Retargeting

Marketing Automation Case Study: Hyper-Targeted Retargeting

Harsh Thakkar image
Harsh Thakkar
Co-Founder & GTM Engineer
January 2, 2026
2 min read

Summarize with

Key Takeaways

Stop wasting ad budget on cold audiences by automating your retargeting funnel with Zapier and Google Sheets. This workflow captures real-time email engagement from Instantly, uses a custom Apps Script to filter for high-intent leads (opens/clicks), and syncs them directly to Google Ads. The result is a zero-touch system that boosts ROI by ensuring you only pay to retarget prospects who have already shown interest.

Marketing Automation Objective:

Improve ROI from cold email campaigns by retargeting only the most engaged leads—those who opened emails multiple times or clicked on links—through a fully automated, no-touch workflow.

Challenge:

Most retargeting strategies waste budget on a broad audience. This client needed a lean system that could identify high-intent prospects in real time and trigger retargeting ads automatically—without manual intervention.

Step 1: Real-Time Engagement Tracking via Zapier

The first step was connecting Instantly with Google Sheets using Zapier to record email engagement as it happened:

  • Email Opened: Each time a recipient opened an email, a row was added in Google Sheets.
  • Link Clicked: If a recipient clicked a link, another row was recorded.

This allowed the marketing team to capture detailed, timestamped insights into each recipient's behavior—without needing to export or sort through campaign reports manually.

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Zap for Instanlty event Trigger

Step 2: Filtering Qualified Leads with Google Apps Script

Every four hours, a custom Google Apps Script reviewed the engagement data and applied predefined logic:

  • Identify contacts who either:
  • Opened the email more than once, or
  • Clicked a link.
  • Move these contacts into a dedicated Filtered Emails sheet.

This ensured that only engaged leads moved forward in the funnel, significantly increasing the chances of conversion and reducing unnecessary ad spend.

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Step 3: Retargeting Engaged Prospects with Google Ads

The Filtered Emails sheet became the basis for a Google Ads Customer Match audience. These qualified leads were automatically added to a custom list that received:

  • Personalized Google Ads
  • Increased frequency of brand impressions
  • Contextually relevant messaging based on prior engagement

This created a seamless pipeline from email outreach to ad retargeting, aligned with actual user interest and behavior.

Conclusion

By integrating real-time engagement tracking, automated lead filtering, and precision-targeted ad campaigns, the client achieved:

  • A sharper focus on high-quality leads
  • Reduced marketing waste
  • Improved ROI from both email and paid channels

This marketing automation workflow not only saved time but also delivered better results by ensuring only the right prospects were retargeted. A perfect example of automation done right.

Marketing Automations#marketing automation#martech#Instantly

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Harsh Thakkar image
Harsh Thakkar
Co-Founder & GTM Engineer

Harsh is the Co-Founder and GTM Engineer at hb.lance. A curious builder and systems thinker helping B2B teams scale through structured GTM systems, clear execution, and data-driven decision-making.

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