Overview

The client experienced discrepancies between Google Ads-reported conversions and the actual number of form submissions. Google Ads showed several conversions even though no real leads were generated. This indicated that the tracking setup was firing inaccurately and counting non-Ads traffic as conversions.

Problem

The Google Ads conversion tag was hard-coded on the thank-you page. This caused every visit to that page—whether from internal testing, direct visits, organic traffic, or users refreshing the page—to be recorded as a conversion. As a result, Google Ads was receiving inflated and unreliable conversion data.

Solution

To fix this, the entire conversion setup was rebuilt using Google Tag Manager. Instead of firing automatically, the conversion now triggers only when the visitor is confirmed to have come from a Google Ads click.

Google adds a unique parameter called a gclid to users who click an ad and stores it in a cookie named _gcl_aw. This cookie persists as the user navigates the site, allowing us to accurately identify Ads-driven sessions.

Inside GTM, we created a trigger that fires the conversion only when:

1. The user reaches the thank-you page, and
2. The _gcl_aw cookie is present (meaning they originally clicked a Google Ad)

This ensures only genuine Google Ads visitors trigger the conversion tag.

Testing and Verification

Both scenarios were tested thoroughly:

• With a valid Google Ads indicator (cookie present) → conversion successfully fired
• Without the indicator (cookie removed or missing) → conversion did not fire

This confirmed the logic was working exactly as intended.

Outcome

Google Ads now receives clean, accurate conversion data. Internal tests, direct traffic, organic visitors, and all non-Ads interactions no longer inflate conversion numbers. The client now has reliable insights for evaluating campaign performance and optimising future ad spend.

Conclusion

By replacing the hard-coded conversion script with a logic-based GTM setup that checks for the Google Ads _gcl_aw cookie, we restored accuracy and integrity to the tracking system. The client can now confidently rely on Google Ads reporting, knowing that only true ad-driven leads are counted as conversions.