Accurate conversion tracking is the foundation of any well-optimised advertising campaign. In an era marked by cookie restrictions and growing privacy expectations, traditional conversion tracking methods are less and less sufficient. To address these challenges, Google Ads offers Enhanced Conversions—a feature that enables more precise attribution of conversions to traffic sources and supports better campaign optimisation.
What are enhanced conversions, and why implement them?
Enhanced Conversions in Google Ads enable more accurate tracking and attribution of conversions on websites. The feature relies on first-party data voluntarily provided by users—such as email addresses, phone numbers, or postal codes—at the point of conversion. This information is securely hashed and sent to Google, allowing the system to better match a user’s action to prior ad interactions. This method works even when standard tracking mechanisms fail—for example, when cookies are blocked or limited by the user’s browser settings.
Key benefits of enhanced conversions
- Increased conversion tracking accuracy: enhanced Conversions help capture more actual conversions that might be missed by traditional methods, especially in cookie-restricted environments.
- Better conversion value attribution: by leveraging first-party data, Google can more accurately associate user actions with specific ad campaigns—even when interactions occur across multiple devices or browsers.
- Improved bidding and budget optimisation: with more precise data, Google Ads algorithms can better optimise campaign performance, resulting in more efficient budget usage and higher return on investment (ROI).
- Cross-device tracking: enhanced Conversions support analysis of user journeys, such as when a user clicks an ad on mobile but completes the conversion on a desktop device.
Data privacy and security
Privacy and data protection are essential when implementing any analytics solution, including Enhanced Conversions. Google has implemented robust safeguards to ensure the security and confidentiality of user information.
Data encryption
All user data is encrypted using a one-way SHA-256 hashing algorithm before being sent to Google, making it unreadable to third parties.
Use of first-party data only
Only information voluntarily provided by users during conversion (e.g. via contact forms) is processed.
Restricted access and use
Google does not share this data with other advertisers or third parties. It is used solely for conversion attribution and performance measurement.
Compliance with legal regulations
The entire process complies with GDPR and other data protection laws. Advertisers must ensure their privacy policies reflect this implementation and obtain user consent where legally required.
Step-by-step implementation with Google Tag Manager and dataLayer
The most recommended method for implementing Enhanced Conversions is through Google Tag Manager (GTM) combined with the dataLayer. This approach is stable, does not rely on changes to CSS/HTML, and minimises performance impact—though it does require developer support. Below is an example based on a form_submission event (e.g., a contact form).
Enabling enhanced conversions in Google Ads
- Log in to Google Ads.
- Navigate to the settings of the selected conversion action.
- Enable the “Enhanced Conversions” option and accept the data processing terms.
Preparing the dataLayer
- Add or request a developer to implement a dataLayer script that triggers upon successful form submission.
- Ensure at minimum the user’s email address is passed through the dataLayer.
- If you intend to send additional fields (e.g., first name), then last name, country, and postal code must also be included—otherwise, GTM will not allow variable configuration.
Example code to be implemented by a developer:
<script>
window.dataLayer = window.dataLayer || [];
window.dataLayer.push({
‘event’: ‘form_submission’,
’email’: ‘user@example.com’
});
</script>
The email value should be dynamically filled based on the form’s input data.
Google Tag Manager configuration
Google recently introduced a new tag type: Google Ads User-Provided Data Event, which now handles Enhanced Conversions.
- Add variables according to the dataLayer fields prepared by your developer.
- In GTM, create a new tag of type Google Ads User-Provided Data Event. Name it, for example, “G.Ads user-provided data.”
- In the tag settings, specify the correct Google Ads conversion ID.
- Under “User-provided data,” create a new variable (e.g., “User-provided data”) and include the dataLayer variables defined earlier.
- The “User-provided Data Event” tag must trigger before the main Google Ads conversion tag. The best practice is to leave the tag without its own trigger and instead sequence it via the advanced settings of the main conversion tag.
- In the conversion tag settings (e.g., “form_submission”), go to Advanced Settings and select Fire a tag before this tag fires. Choose the “G.Ads user-provided data” tag here.
Testing the setup
- Enter GTM Preview mode and submit a test form.
- In the GTM console or preview pane, confirm that the parameter em (email) appears in the data payload and is hashed (should begin with tv.1~em). This confirms the tag is correctly capturing and encrypting the email address.
- You can also verify implementation using the EC Assist tool.
- Once validated, publish the GTM container.
Key data requirements
- Email address is the primary and most reliable identifier.
- If additional user data (like first name) is to be included, then last name, country, and postal code are mandatory. GTM will not accept the variable otherwise.
Alternative implementation methods
While the dataLayer method is recommended for its stability, GTM also supports other approaches to pass user data for Enhanced Conversions. However, these are more fragile and less maintainable:
- Automatic data capture – GTM can attempt to extract user data directly from the form using CSS selectors or JavaScript (e.g., document.querySelector(“input[name=’email’]”).value). Although fast and developer-free, this method is error-prone. Any changes to form structure—such as class names or field layouts—can break tracking.
- JavaScript variables – Manually pulling values from the DOM is relatively simple but equally unstable. Frequent frontend updates may disrupt these variables and prevent conversions from being recorded correctly.
Summary
Implementing Enhanced Conversions via GTM and dataLayer is currently the most secure, accurate, and robust method for optimising Google Ads campaigns. It ensures accurate conversion attribution, even in privacy-first environments, and aligns with data protection laws. Investing the time to configure this properly pays off in better data and a meaningful competitive edge.
If you’re unsure whether Enhanced Conversions are right for your organisation—or if you need support with implementation—fill out the contact form below. Our analytics team will assess your business needs, recommend an optimal implementation path, and ensure every element is configured correctly.
