This guide walks you through configuring Google Ads Conversions and Google Ads Remarketing using a server-side Google Tag Manager (GTM) container provisioned by Seers.
Prerequisites
Before getting started, make sure the following are in place:
- Google Ads: Access to a Google Ads account. This will be needed for testing events. Refer to Google's documentation for guidance on how to share account access.
- Google Ads Conversion ID and Conversion Label: Retrieve these values directly from your Google Ads account.
- Web Google Tag Manager (GTM): A web GTM container that is already live on your website and is configured to send GA4 events to your server-side GTM instance. Refer to Google's documentation on how to share access to a GTM container.
- Server-Side GTM Container (Seers): A server-side GTM container provisioned by Seers, accessible via a first-party endpoint, and set up to handle GA4 events. Visit the Seers Get Started Guide to learn how to configure your server-side GTM, and refer to the GTM documentation for sharing container access.
Why Use Server-Side Tagging with Google Ads?
Improved Data Accuracy
Server-side tagging routes data through your own server rather than the user's browser, bypassing ad blockers and browser-level privacy restrictions such as Safari's Intelligent Tracking Prevention (ITP) or Firefox's Enhanced Tracking Protection (ETP). This leads to more complete and reliable conversion data.
Better Website Performance
By moving tracking logic off the browser and onto the server, you significantly reduce the amount of JavaScript that needs to load in the user's browser. This consolidates outbound data requests into a single, efficient stream, resulting in faster page loads and a smoother user experience.
Stronger Data Control
With server-side tagging, you have full control over what information is shared with Google. You can enrich, filter, or anonymise data to meet privacy requirements such as GDPR or CCPA. Additionally, reducing client-side JavaScript can ease pressure on the browser's main thread, improving Core Web Vitals scores and potentially boosting SEO performance.
Implementation Overview
The setup involves creating three tags: a Conversion Linker tag, a Google Ads Remarketing tag, and a Google Ads Conversion tag.
- Conversion Linker Tag: This tag is a prerequisite for accurate conversion measurement in Google Ads. It reads ad click data from landing page URLs and stores it in a first-party cookie on your domain. This ensures that click attribution data is not lost due to third-party cookie restrictions in modern browsers. It should be configured to fire on every page of your website.
- Google Ads Remarketing Tag: This tag builds audience lists from your website visitors by tracking user behaviour and reporting it back to your Google Ads account. It powers both standard and dynamic remarketing campaigns, allowing you to serve relevant ads to users who have already interacted with your site.
- Google Ads Conversion Tag: This tag tracks specific actions users take on your site, such as completing a purchase or submitting a form, and reports them to Google Ads. This attribution data helps you understand which campaigns are driving results and supports smarter bidding strategies.
Together, these three tags capture a complete user journey: the Conversion Linker preserves the ad click ID, the Remarketing tag records the user's interest in specific content, and the Conversion tag reports back on the campaign's effectiveness.
Step 1: Configure the Conversion Linker Tag
- Open your server-side GTM container and navigate to Tags, then click New.
- From the list of available built-in tag types, select Conversion Linker.
Accept Incoming Linker Parameters (Optional)
When enabled, this setting instructs the server-side tag to detect and process linker parameters (such as_gl) from incoming URLs. Enable this option when your user journey crosses multiple domains, and you need to carry ad click data between sites for accurate attribution. If your setup is single-domain only, you can leave this unchecked.
Override Cookie Settings (Advanced, Optional)
This setting gives you direct control over the name, domain, and path of the first-party cookie that the tag creates. It is only needed for specific, advanced scenarios, such as resolving cookie naming conflicts or limiting a cookie's scope to a particular subdomain. For most implementations, the default settings are sufficient.
- Configure the trigger so the Conversion Linker fires on every incoming request that may carry ad click information. The recommended approach is to use an All Pages trigger (or its equivalent) in the server container, so the tag runs on all page view events.
- Give the tag a clear, descriptive name (for example, "Conversion Linker") and click Save.
Step 2: Configure the Google Ads Remarketing Tag
If you are migrating an existing Google Ads Remarketing tag from a web GTM container, use the Conversion ID from that existing web tag. Otherwise, follow the steps below to retrieve it.
Retrieve Your Google Ads Conversion ID
- Sign in to your Google Ads account and go to Tools & Settings > Shared Library > Audience Manager.
- Select Your Data Sources and locate the Google Ads tag card.
- Click Details, then navigate to Tag Setup.
- Under the Use Google Tag Manager section, you will find your Conversion ID. Copy this value.
Create the Remarketing Tag in the Server Container
- In your server-side GTM container, click Tags in the left-hand menu, then click New.
- Select Google Ads Remarketing from the list of available tag types.
- In the Tag Configuration panel, paste the Conversion ID you retrieved from Google Ads.
Enable Dynamic Remarketing (Optional)
The Send dynamic remarketing event data option passes specific product and user data along with your remarketing events. Enable this when you want to serve personalised ads based on the exact products or content a user engaged with on your site.
- Check the box for Send dynamic remarketing event data in the tag configuration.
- Under Data Source, the default Event Data option is typically sufficient if your dataLayer and GA4 events follow the standard e-commerce schema (e.g., view_item, add_to_cart). The tag will automatically extract parameters like item_id, value, and currency.
- If your dataLayer does not use the standard schema, select Custom configuration and manually map Google Ads parameters (ecomm_prodid, ecomm_pagetype, etc.) to variables from your incoming GA4 event data. You will need to create User-Defined Variables in the server container to extract these values.
Enable Restricted Data Processing (Optional)
Activate this setting to help meet the requirements of privacy regulations such as the CCPA, which gives users the right to opt out of the sale of their personal data. When enabled, it signals to Google to restrict how it processes and uses a user's data, limiting its use for personalised advertising.
Enable Custom Parameters (Optional)
Use this setting to include additional, non-standard data with your Google Ads events. This is useful when you need to pass specific custom information, such as a user's subscription plan or a product's brand, that is not part of the default event payload, for use in reporting or audience building.
Enable User ID Passthrough (Optional)
This option allows you to send a unique user identifier to Google Ads. If you maintain a proprietary user ID system, passing it here enables cross-device and cross-platform attribution, helping Google more accurately link conversions to users who are signed in across multiple devices.
- Ensure that Enable Conversion Linking is set to true.
- Under Triggering, select a trigger that fires on All Pages or equivalent, typically a trigger covering all GA4 client events or all incoming page_view requests in the server container.
- Name the tag clearly (for example, "Google Ads Remarketing") and click Save.
Step 3: Configure the Google Ads Conversion Tag
If you are migrating an existing Google Ads Conversion tag from a web GTM container, use the Conversion ID and Conversion Label from that web tag. Otherwise, follow the steps below to retrieve your conversion details.
Retrieve Your Conversion Information from Google Ads
- In your Google Ads account, navigate to Tools & Settings > Measurement > Conversions.
- Select the conversion action you want to track (e.g., "Purchase" or "Form Submission").
- Click the conversion action name to open its details.
- Expand the Tag setup section and choose Use Google Tag Manager.
- Copy both the Conversion ID and the Conversion Label displayed here.
Create the Conversion Tag in the Server Container
- In your server-side GTM container, go to Tags in the left navigation and click New.
- Choose Google Ads Conversion Tracking as the tag type.
- Paste the Conversion ID and Conversion Label you copied from Google Ads into the Tag Configuration fields.
Set Up Event Data
- Conversion Value: For conversions with a monetary value (such as purchases), click the + icon next to this field and select a User-Defined Variable that extracts the transaction value from the incoming GA4 event data (for example, from the value parameter).
- Currency Code: Add a variable that reads the currency code from the incoming GA4 event data.
Enable Restricted Data Processing (Optional)
As with the Remarketing tag, enabling this setting helps you comply with privacy regulations such as the CCPA and GDPR. It signals to Google to limit its use of user data and prevents it from being applied to personalised advertising.
Enable Product-Level Sales Data (Optional)
This option lets you send detailed product-level information for each transaction, not just the overall conversion value. Enable it for e-commerce sites to unlock advanced reporting in Google Ads, including revenue and profit breakdowns by product, cart size analysis, and cross-sell insights. This data is particularly valuable for Shopping and Performance Max campaign optimisation.
Enable New Customer Data (Optional)
Use this setting to flag whether a converting user is new or returning. Providing this signal helps Google Ads inform bidding strategies and campaign reporting, enabling you to optimise for new customer acquisition, which is often prioritised over returning customers in growth-focused strategies.
- Confirm that Enable Conversion Linking is set to true.
- Under Triggering, select or create a trigger that fires only for your specific conversion event, for example, a purchase event trigger.
- Name the tag descriptively (for example, "Google Ads Conversion") and click Save.
Step 4: Testing, Debugging, and Publishing
Before publishing your changes, use the server-side GTM Preview Mode to thoroughly test each tag. Verify that:
- Each tag fires at the correct point in the user journey.
- The expected data is being sent with each event.
- There are no unexpected errors or data discrepancies.
Running these checks proactively helps you catch issues early and ensures your campaign measurement is accurate from day one. Once you are satisfied with the tag behaviour in Preview Mode, publish your workspace to make the changes live.
| Note: If you have migrated your Google Ads tags from your Web GTM container to your server-side Tag Manager, make sure to disable or remove those original tags from the Web GTM container to prevent duplicate data from being sent to Google Ads. |