Google Ads Conversion Tracking Using Google Tag Manager (2025 New Interface)

From “Flying Blind” to Data-Driven Confidence

Are you tired of pouring money into Google Ads and feeling like you’re “flying blind”? It’s a common and deeply frustrating experience for marketers. Campaigns are running, clicks are accumulating, and the budget is being spent, but a nagging question remains: what’s actually working? This uncertainty leads to anxiety about wasted ad spend and the fear that money is being left on the table. Without clear data, decision-making is based on guesswork, and proving the value of marketing efforts feels nearly impossible.

This guide is designed to change that. Its promise is to walk through the process of setting up Google Ads conversion tracking using Google Tag Manager, step-by-step. While the process can seem technically intimidating, it is absolutely achievable. This guide will point out the common pitfalls so they can be avoided, helping build a tracking system that can finally be trusted. True confidence, however, comes not just from a technically sound setup, but from a deep understanding of why specific actions are being measured. By integrating a strategic measurement framework with the technical “how-to,” this guide offers a complete path forward. By the end, marketers will have a foundation for making smart, data-driven marketing decisions, optimising campaigns for real results, and confidently demonstrating the return on investment.

Understanding the ‘Why’ Before the ‘How’

Before diving into the technical setup within Google Ads and Google Tag Manager, it is critical to establish a strategic foundation. The biggest mistake in measurement is starting with tools without first knowing what questions need to be answered. This section bridges that gap by integrating principles from the Actionable Measurement Framework, ensuring every technical step taken is grounded in a clear business purpose.

What is a Conversion? The Heart of Your Business Outcome

In the context of Google Ads, a conversion is not merely a technical event like a click or a page view. A conversion is a specific, valuable action a user takes that directly contributes to a desired Business Outcome . Every website exists to achieve outcomes, whether it’s growing sales revenue, increasing qualified leads, or building an engaged community. The conversion is the tangible user behaviour that makes that outcome happen. For example, the business outcome might be to “increase qualified leads.” The conversion action that facilitates this is a user successfully submitting a “Request a Quote” form. Reframing the goal in this way, from a technical task (“track form fills”) to a strategic objective (“measure the behaviour that generates leads”), is the first and most important step toward meaningful measurement.

Why is Tracking Conversions Crucial?

Without conversion tracking, marketers are operating on intuition and vanity metrics like clicks and impressions, which say little about actual business impact. This is the digital equivalent of “flying blind.” There are two primary, unassailable reasons why robust conversion tracking is essential for any serious advertiser.

First, conversion tracking is necessary to enable Google Ads optimisation . Google’s Smart Bidding strategies, such as Target CPA, Target ROAS, and Maximise Conversions, are powerful machine learning algorithms. However, these algorithms are “starving for insights” if they are not fed accurate data. Conversion data is the fuel that allows these systems to learn which users, keywords, ads, and audiences are most likely to drive real business results. Without it, the algorithm can only optimise for clicks, which often do not correlate with sales or leads, leading to inefficient and wasted ad spend.

Second, conversion tracking provides the data needed to answer Key Performance Questions (KPQs) . The true purpose of analytics is not to generate reports, but to answer important business questions that guide strategy. Conversion data is the raw material for these answers. KPQs are the questions that, when answered, provide the knowledge needed to improve results. Examples of KPQs that conversion tracking helps answer include:

• “Which marketing channels are most effective at driving qualified leads?”
• “What is our overall sales conversion rate from paid search?”
• “What is the return on ad spend (ROAS) for our top campaigns?”
• “Which ad copy variations lead to the highest-value customers?”

Answering these questions transforms a marketer from a campaign operator into a strategic business driver.

Macro vs. Micro Conversions (The ARC Framework)

Not all conversions are created equal. To understand their relative value, it is helpful to use the ARC (Aware, Review, Convert/Complete) framework, which maps the typical user journey.

• Aware: How users discover a business (e.g., through a search ad).
• Review: How users evaluate the offer (e.g., by reading product pages, watching a demo, or downloading a whitepaper).
• Convert/Complete: When users take the final action that achieves the business outcome (e.g., making a purchase or submitting a lead form).

This framework provides a powerful mental model for categorising conversions and, critically, for telling Google Ads what to prioritise.

Macro-Conversions

A macro-conversion is the primary goal, the most valuable action a user can take. These are the behaviours that occur in the Convert/Complete stage of the journey, such as a completed purchase or a submitted “Contact Us” form. Because these actions directly generate revenue or qualified leads, they are the actions that Google’s bidding algorithms should be optimised for. This strategic concept maps directly to a critical technical setting in Google Ads. When setting up a conversion action, macro-conversions should almost always be configured as “Primary” actions . This explicitly tells Google’s Smart Bidding to find more people who are likely to perform this high-value action, aligning the campaign’s optimisation directly with the core business objective.

Micro-Conversions

A micro-conversion is a valuable secondary action that indicates a user is moving through the Review stage of their journey. These are important engagement behaviours that often precede a macro-conversion. Examples include signing up for a newsletter, downloading a case study, watching a product demo video, or adding an item to a cart. While these actions are valuable signals of interest, they are not the ultimate goal. Optimising a campaign for newsletter signups could inadvertently de-prioritise the more valuable goal of actual sales. Therefore, micro-conversions should typically be set as “Secondary” actions in Google Ads. This allows the marketer to track and observe these important engagements, and use them to answer behavioural KPQs like “Which content keeps visitors engaged longest?”, without having them influence the primary bidding strategy. This distinction prevents the algorithm from optimising for a lower-value goal at the expense of the one that truly drives the business forward.

Prerequisites: What You Need Before You Start

Before we dive in, let’s make sure you have your keys. This quick checklist will ensure a smooth setup process. Having these three elements ready will save you a lot of time and potential headaches.

• An active Google Ads account: This is your command centre, where you’ll define your conversion goals and analyse campaign performance.
• An active Google Tag Manager (GTM) account: GTM is the free tool we’ll use to add tracking codes (known as “tags”) to your website without needing to edit the site’s code directly every time. It’s the modern, flexible, and recommended way to manage all your tracking snippets. Critically, the main GTM container snippet must already be installed on every page of your website.
• Access to your website’s backend: You’ll need this to get the GTM container snippet installed initially. If you have a developer, now is a great time to make sure they’re on standby to help if needed.

Creating Your First Conversion Action: A Step-by-Step Walkthrough

The first critical step in the technical setup happens inside the Google Ads platform, not Google Tag Manager. This is where the “goal” or “conversion action” is defined. By following the strategic principles outlined above, each setting chosen in this section will be a deliberate, informed decision.

To begin, a new conversion action must be created within the Google Ads account.

1. Sign in to your Google Ads account.
2. Look to the left of the screen and click Goals > Conversions > Summary.

Click the New conversion action button. The location of the button varies depending on if the are existing conversion actions or not. The image below are how it looks when there are no existing conversion actions.

You’ll now see four main categories. We’re going to break down each one, explaining what it’s for and how to set it up with a special focus on using Google Tag Manager.

Types of Conversion Actions and Their GTM Compatibility

Google will ask to select the kind of conversions to track. Before selecting one, it is helpful to understand the main types and how they relate to Google Tag Manager (GTM), the tool this guide focuses on.

Conversion Type	Description	Can it be tracked with GTM?
Conversions on a website	Measures valuable actions users take on your website, such as purchases, lead form submissions, or newsletter sign-ups.	Yes (Recommended). This is the most common use case for GTM. It allows you to deploy and manage tracking tags without editing website code.
Conversions on an app	Tracks app installs and in-app actions, like completing a level or making a purchase within your mobile app.	Yes (Advanced). While app tracking is primarily done via the Firebase SDK, GTM has mobile containers that integrate with Firebase to manage event tags.
Conversions from phone calls	Tracks calls to your business that originate from your ads, either directly from an ad or from your website after an ad click.	Yes. GTM is used to deploy the code that dynamically swaps your business number with a trackable Google Forwarding Number on your website.
Conversions offline	Measures conversions that start online with an ad click but are completed offline, such as a deal closed in-store or over the phone.	Yes (Indirect but Crucial). GTM is used to capture the Google Click ID (GCLID) from the URL and pass it into a hidden field in your lead forms for later use.

For this guide, the focus is on the most common and crucial type for most businesses: Website. Select it, enter the website domain, and click Scan.

Website Conversions

This is the most common and fundamental type of conversion you’ll track. It measures valuable actions that happen directly on your website.

Use Case: This is perfect for tracking e-commerce purchases, lead form submissions, newsletter sign-ups, or downloads of a PDF.  

Walkthrough Example: Creating a “Purchase” Conversion Action

• Tick the Checkbox for the Conversions on a website options.

• Enter your website domain (e.g., yourbusiness.com) and click Scan. Google will check your site for its tracking tag.

After the scan, scroll down and click + Add a conversion action manually. This gives us full control over every setting, which is exactly what we want.  

Now, let’s configure the settings. This part is crucial, as these choices tell Google Ads not just what to track, but how to value it and use it for optimisation.

Choosing Your Settings (and What They Actually Mean)

After scanning the site, Google will present options to create a conversion action. It is best to set it up manually to have full control and understanding. Scroll down and click + Add a conversion action manually. This is where many marketers feel overwhelmed, but each setting has a clear purpose tied directly to business goals.

• Goal and action optimisation: This setting is how instructions are given to Google on what is most valued. As discussed in the previous section, Primary actions are used for bidding optimisation, while Secondary actions are for observation only. For a core business goal like a contact form submission or a purchase (a macro-conversion), this should be set to Primary.

• Name:

• Value: This setting is critical for calculating return on investment (ROI).
  • Use the same value for each conversion: This is best for lead generation, where each lead has a similar estimated worth. Even an estimate is far better than zero. A simple way to calculate this: if it is known that 1 in every 10 leads turns into a customer worth $500, then the value per lead is $50. This single step is the foundation for proving marketing ROI.
  • Use different values for each conversion: This is the standard for e-commerce, where the value of each purchase varies. This option requires a dynamic setup where the actual purchase total and currency are pulled from the website’s data layer on the confirmation page and passed into the conversion tag. This often requires developer assistance or a pre-built e-commerce integration.
  • Don’t use a value: This is not recommended, as it prevents the measurement of ROI.

• Count: This setting determines how conversions are counted after a single ad interaction.
  • Every: This should be chosen for sales or purchases. If a customer clicks an ad and buys three different items in three separate transactions, all three should be counted as valuable conversions.
  • One: This should be chosen for leads. If the same person gets excited and fills out the contact form three times in one session, it is likely desirable to count that as only one new lead. This setting prevents the inflation of lead generation numbers.

• Attribution model: In simple terms, attribution is how Google decides which ad click gets credit for a conversion when a customer interacts with multiple ads. Google’s default and recommended setting is Data-driven, which uses machine learning to assign credit based on how people engage with the various ads. For now, it is best to stick with this default. The primary goal is to get the tracking working correctly; attribution can be explored in more detail later once reliable data is flowing.

The table below provides a quick “cheat sheet” for these settings based on common business goals.

Setting	What it Means	Recommendation for E-commerce	Recommendation for Lead Gen
Action optimisation	This decides if the conversion helps Google’s AI optimize your bids (Primary) or is just for your observation (Secondary).	Primary	Primary
Conversion name	A clear, descriptive name for your action that will appear in your reports (e.g., “Main Website Purchase”).
Value	This is how much a conversion is worth to your business. It can be a fixed amount or a dynamic amount that changes with each sale.	Use different values for each conversion (requires dynamic setup).	Use the same value for each conversion (based on an estimate).
Count	This setting asks if you want to count every conversion from one person (like multiple purchases) or just one (like a single lead form submission).	Every	One
Attribution Model	This determines how credit for a conversion is given to your ads along the customer’s journey.	Data-driven (Default)	Data-driven (Default)

Getting the Conversion ID and Label

On the next screen, you’ll see setup instructions. Click the tab that says Use Google Tag Manager. This is our preferred, most flexible method.  

You will be given two critical pieces of information: a Conversion ID and a Conversion Label. Copy these to a notepad; they are the keys that link GTM to this specific conversion action.  

If you clicked Agree and finish and forgot to note the Conversion ID and Conversion label, fear not, you can get them from the newly created Conversion Action.

1. Click on the newly created conversion action.
2. Under “Tag setup,” click the Use Google Tag Manager tab.
3. The Conversion ID and the Conversion Label. will now be visible.

Think of these as the unique address for the conversion. The Conversion ID is like a building’s street address; it’s the same for all conversions in the account. The Conversion Label is like the specific apartment number; it’s unique to this specific conversion action just created. Both of these are needed to tell Google Tag Manager exactly where to send the “success” signal. Keep this browser tab open or copy these values somewhere safe. They will be needed in the next part.

A Primer on Enhanced Conversions

Before moving to tag setup, it is important to understand a crucial feature called Enhanced Conversions. In an online world with increasing privacy regulations and the phasing out of third-party cookies, traditional tracking methods are becoming less reliable. Enhanced Conversions is Google’s solution to this challenge.

Conceptually, it is a feature that improves tracking accuracy by securely sending hashed, first-party data from a website to Google after a conversion occurs. This data can include an email address, phone number, or home address. The data is hashed using a secure one-way algorithm called SHA256 before it leaves the user’s browser, meaning it is anonymised and privacy-safe. Google then uses this hashed data to match conversions back to ad clicks, even when traditional identifiers like cookies are not available. This helps to “recover” conversions that would otherwise be lost, leading to more complete and accurate data, which in turn fuels smarter, more effective bidding.

While the detailed implementation of Enhanced Conversions is an advanced topic that often requires modifications to a website’s data layer, turning the feature on within the Google Ads UI is the first step. This signals the intent to use this more robust tracking method.

The Two Most Important Tags in Google Tag Manager

With the goal defined in Google Ads, it is time to move to Google Tag Manager (GTM). Here, the foundational tags that make all tracking work reliably will be set up. Getting these two tags right will prevent the most common and costly tracking errors. This approach represents a modern shift from adding single-purpose tags to establishing a robust, sitewide “tagging infrastructure” first.

The Conversion Linker Tag – Your Key to Accurate Attribution

The Conversion Linker tag is non-negotiable for accurate tracking in the modern web. Its purpose is to help Google reliably connect the ad click that brought a user to a site with the conversion they complete later. In the past, this connection was made using third-party cookies. However, due to increased privacy regulations and browser changes like Safari’s Intelligent Tracking Prevention (ITP), the use of third-party cookies is being phased out. The Conversion Linker is Google’s solution. It works by storing the ad click information (specifically, the Google Click ID or GCLID) in a first-party cookie on the site’s own domain. This method is more durable, more privacy-compliant, and essential for making tracking work in today’s internet landscape. This tag is not just a technical step; it is a strategic adaptation to future-proof attribution.

Missing or misconfiguring this tag is one of the most frequent errors marketers make. It directly leads to underreported conversions in Google Ads. When Google Ads does not receive accurate conversion data, its automated bidding strategies cannot optimise properly, which means money is wasted on campaigns that appear to be underperforming. While some newer documentation suggests the main Google Tag can handle this function, the established best practice is to always include a separate Conversion Linker tag. It costs nothing and acts as a vital insurance policy for attribution, guaranteeing this crucial function is performed correctly.

How to set it up:

1. In the Google Tag Manager container, navigate to Tags in the left-hand menu and click New.
2. Name the tag something clear, like “Google Ads – Conversion Linker”.
3. Click on Tag Configuration.
4. From the list of tag types, choose Conversion Linker. No further configuration is needed in this section.
5. Next, click on Triggering.
6. Select the built-in All Pages trigger. This ensures the tag can capture click information no matter which page a user lands on from an ad.
7. Click Save.

The Google Tag – Building Your Audiences and Powering Conversions

The next foundational piece is the “Google Tag.” This may be referred to in older guides as the “Google Ads Remarketing Tag,” but it has evolved to become the central tag for all Google Ads tracking and audience building. This clarification is important, as searching for the old name can lead to confusion.

This tag performs two critical jobs. First, it places a tracking pixel on every page of the site, which allows for the building of remarketing audiences. This means targeted ads can later be shown to people who have visited the site, viewed specific products, or taken other actions. Second, it acts as the foundational tag that specific conversion tags (like the one that will be created in Part 3) rely on to function correctly. It only needs to be installed once.

Find Google Tag in Google Ads Account:

How to set it up:

1. In GTM, go to Tags and click New.
2. Name the tag “Google – Google Tag”.
3. Click on Tag Configuration and select Google Ads.
4. From the options that appear, choose Google Tag.
5. A field for Tag ID will appear. Here, paste the Conversion ID from Google Ads (the one starting with “AW-“) that was saved in Part 1.
6. Click on Triggering and select the All Pages trigger.
7. Click Save.

With these two tags configured to fire on all pages, a solid and reliable foundation has been built for all Google Ads tracking. This infrastructure ensures attribution integrity across the entire site and establishes the presence needed for both conversion tracking and audience building. Specific conversion events can now be layered on top of this robust platform.

Tracking Specific Conversions

Method 1: The Data Layer

The most robust, accurate, and scalable method for tracking conversions is to use a data layer. This approach involves a developer pushing a small snippet of JavaScript to the data layer when a conversion occurs, which GTM then uses as a trigger.

The “Why”: A Deeper Dive into Data Layer Superiority

Choosing to implement a data layer is a shift from a tactical “tag-on-page” mindset to a strategic approach to data architecture. The benefits are substantial and address the core weaknesses of older methods.

• Reliability: Tracking is decoupled from the website’s presentation layer (HTML/CSS) and URL structure. If your marketing team decides to change the thank you page URL from /thank-you to /order-confirmation, a URL-based trigger will silently break. A data layer event, however, will continue to fire correctly as long as the developer pushes the same event name, making your tracking resilient to website redesigns and content updates.  
• Data Richness: This is the most significant advantage. A URL alone cannot convey dynamic, transaction-specific information. The data layer can carry a wealth of contextual data, such as unique transaction IDs to prevent duplicate conversions, precise revenue values for ROAS calculations, currency codes, and even detailed product information. This rich data unlocks more sophisticated reporting, audience building, and optimization capabilities within Google Ads.  
• Scalability & The Single Source of Truth: A well-structured, GA4-compatible data layer becomes a universal data bus for your website. The same purchase event can be used as a trigger for the Google Ads conversion tag, a GA4 ecommerce tag, a Meta Pixel purchase event, and any other marketing or analytics platform. This practice eliminates redundant tracking code, reduces the risk of data discrepancies between platforms, and ensures all systems are reporting based on the same foundational event, creating a scalable and maintainable tracking architecture.  

The following table provides an at-a-glance comparison to help illustrate these points when discussing implementation with stakeholders.

Feature	Data Layer Method (Recommended)	Thank You Page Method (Fallback)
Reliability	High. Independent of URL changes and website redesigns.	Low. Brittle; breaks if the “Thank You” page URL is changed.
Data Richness	High. Can pass dynamic transaction IDs, values, currency, etc.	Very Low. Cannot easily pass dynamic values. Static values only.
Accuracy	High. Captures the event at the moment of conversion.	Moderate. Can misfire on page reloads or accidental visits.
Scalability	High. Creates a single event to trigger multiple marketing tags.	Low. Requires separate logic for each marketing platform.
Future-Proofing	High. Aligns with modern, event-driven analytics (GA4).	Low. A legacy approach that is incompatible with modern web apps.

Purchase Event Setup: Tracking Ecommerce Success

For an ecommerce transaction, the goal is to capture the purchase event along with its unique ID, value, and currency.

The Developer Handoff: The Data Layer Snippet

Provide the following JavaScript snippet to your developer. It should be executed on the confirmation page immediately after a successful transaction is processed. The values for transaction_id, value, and currency must be populated dynamically from your backend system. This structure is compatible with the official Google Analytics 4 purchase event schema, ensuring forward compatibility.

<script>
  window.dataLayer = window.dataLayer || [];
  window.dataLayer.push({
    event: 'purchase',
    ecommerce: {
        transaction_id: 'T_12345', // E.g.: Unique ID for the transaction
        value: 75.25,             // E.g.: Total transaction value, including tax and shipping
        currency: 'USD',          // E.g.: The currency of the transaction
        items: [
          {
            item_id: 'SKU_001',   // E.g.: Product SKU or ID
            item_name: 'Cool T-Shirt', // E.g.: Product Name
            price: 25.00,         // E.g.: Price per unit
            quantity: 2           // E.g.: Quantity of this item
          },
          {
            item_id: 'SKU_002',
            item_name: 'Awesome Hat',
            price: 25.25,
            quantity: 1
          }
        ]
    }
  });
</script>

GTM Configuration: Step-by-Step

Once the data layer is in place, configure GTM to read this information and send it to Google Ads.

1. Create Variables

First, create variables in GTM to capture the dynamic values from the data layer.

• Navigate to Variables > User-Defined Variables > New.
• Variable 1: Transaction ID
  • Variable Type: Data Layer Variable
  • Variable Name: dlv – ecommerce.transaction_id
  • Data Layer Variable Name: ecommerce.transaction_id
  • Save the variable.
• Variable 2: Transaction Value
  • Variable Type: Data Layer Variable
  • Variable Name: dlv – ecommerce.value
  • Data Layer Variable Name: ecommerce.value
  • Save the variable.
• Variable 3: Transaction Currency
  • Variable Type: Data Layer Variable
  • Variable Name: dlv – ecommerce.currency
  • Data Layer Variable Name: ecommerce.currency
  • Save the variable.

2. Create the Trigger

Next, create a trigger that listens for the custom purchase event.

• Navigate to Triggers > New.
• Trigger Type: Custom Event
• Trigger Name: custom – purchase
• Event Name: purchase
• Leave the trigger to fire on “All Custom Events”.
• Save the trigger.

3. Create the Tag

Finally, create the Google Ads tag that will send the conversion data.

• Navigate to Tags > New.
• Tag Type: Google Ads Conversion Tracking
• Tag Name: Google Ads – Conversion – Purchase
• Conversion ID: Enter your Google Ads Conversion ID.
• Conversion Label: Enter the Conversion Label for your purchase action.
• Conversion Value: Click the variable icon and select {{dlv – ecommerce.value}}.
• Transaction ID: Click the variable icon and select {{dlv – ecommerce.transaction_id}}.
• Currency Code: Click the variable icon and select {{dlv – ecommerce.currency}}.
• Triggering: Click the triggering section and select the custom – purchase trigger you created.
• Save the tag.

Lead Event Setup: Capturing High-Value Interest

For lead generation, the process is similar but simpler, as you may not always have a dynamic value.

The Developer Handoff: The Data Layer Snippet

Provide this snippet to your developer to be executed upon a successful form submission (e.g., within the form’s “on-success” JavaScript callback). This uses the GA4-recommended generate_lead event name.  

<script>
  window.dataLayer = window.dataLayer || [];
  window.dataLayer.push({
    event: 'generate_lead',
    value: 50.00,     // E.g.: The monetary value of the lead
    currency: 'USD'   // E.g.: The currency for the value
  });
</script>

GTM Configuration: Step-by-Step

1. Create Variable (Optional)

If you are assigning a value to your leads, create a variable to capture it.

• Navigate to Variables > User-Defined Variables > New.
• Variable Type: Data Layer Variable
• Variable Name: dlv – lead_value
• Data Layer Variable Name: value
• Save the variable.

2. Create the Trigger

• Navigate to Triggers > New.
• Trigger Type: Custom Event
• Trigger Name: Custom Event – generate_lead
• Event Name: generate_lead
• Save the trigger.

3. Create the Tag

• Navigate to Tags > New.
• Tag Type: Google Ads Conversion Tracking
• Tag Name: Google Ads – Conversion – Generate Lead
• Conversion ID: Enter your Google Ads Conversion ID.
• Conversion Label: Enter the Conversion Label for your lead action.
• Conversion Value: If you created the variable, select {{dlv – lead_value}}. Otherwise, you can leave this blank or enter a static average value.
• Currency Code: If you are sending a value, enter the appropriate currency code (e.g., USD).
• Triggering: Select the Custom Event – generate_lead trigger.
• Save the tag.

Method 2: The Thank You Page

This method should only be used as a last resort when implementing a data layer is technically infeasible or not possible within project constraints. It relies on a user visiting a specific confirmation or “thank you” page after completing an action.

Explaining the Inherent Limitations

While simple to set up, this method comes with significant drawbacks that compromise data quality:

• Brittle and Unreliable: The tracking is entirely dependent on the URL. If a developer or content manager changes the URL from /thank-you to /form-success, your tracking will instantly and silently break.  
• Inaccurate Firing: A user who bookmarks the thank you page and revisits it later, or simply refreshes the page, can trigger a duplicate conversion. This pollutes your data with false positives and makes it difficult to trust your conversion counts.
• No Dynamic Data: This is the most critical limitation. You cannot easily pass dynamic, transaction-specific data like the exact purchase value or a unique transaction ID. This makes accurate ROAS calculation impossible and removes the ability to deduplicate conversions on the Google Ads side.  

GTM Configuration: Step-by-Step

If you must use this method, follow these steps.

1. Create the Trigger

• Navigate to Triggers > New.
• Trigger Type: Page View
• Trigger Name: Page View – Thank You Page
• Set the trigger to fire on Some Page Views.
• Configure the firing condition as follows:
  • Page URL | contains | /thank-you
• Note: Be as specific as possible with the URL string to minimize the risk of the trigger firing on other pages that might contain the same word (e.g., a blog post about thank you pages).
• Save the trigger.

2. Create the Tag

• Navigate to Tags > New.
• Tag Type: Google Ads Conversion Tracking
• Tag Name: Google Ads – Conversion – Thank You Page
• Conversion ID: Enter your Google Ads Conversion ID.
• Conversion Label: Enter the appropriate Conversion Label.
• Conversion Value / Transaction ID: Leave these fields blank or enter a static average value for your conversions. Acknowledge that this sacrifices data precision.
• Triggering: Select the Page View – Thank You Page trigger you created.
• Save the tag.

Testing & Verification

The golden rule of tag management is to never publish blindly. Testing is a mandatory step to ensure your implementation is working as expected before it goes live and begins influencing your ad spend.

Using GTM’s Preview Mode (Tag Assistant)

Google Tag Manager’s built-in Preview Mode is an indispensable tool for debugging your setup.  

1. In the top-right corner of your GTM workspace, click Preview.
2. A new browser tab will open for the Tag Assistant. Enter your website’s URL and click Connect.
3. Your website will open in a new tab with the Tag Assistant debug pane connected.
4. On your website, perform the action required to trigger the conversion (e.g., complete a test purchase or submit a lead form).
5. Return to the Tag Assistant tab to analyze the results.

What to Look For (Data Layer Method)

• In the left-hand event summary, click on your custom event name (e.g., purchase or generate_lead).
• Under the “Tags Fired” section, verify that your Google Ads Conversion Tracking tag is listed.
• Click on the tag to inspect its details. Select the Variables tab in the tag details view.
• Confirm that your data layer variables (dlv – ecommerce.value, etc.) are populated with the correct, dynamic data from your test transaction.  

This ability to inspect the data layer directly is a powerful feature. It transforms tracking from a “black box” into a transparent process. If a developer has missed a key in the dataLayer.push(), a marketer can now provide a precise, actionable bug report (“The transaction_id key is missing from the purchase event”) instead of a vague “tracking is broken” message. This fosters better collaboration and accountability.

What to Look For (Thank You Page Method)

• In the left-hand event summary, navigate to the Container Loaded event that corresponds to your thank you page URL.
• Verify that your Google Ads Conversion Tracking tag is listed under “Tags Fired” for this event. There will be no dynamic data to inspect.

Now for the rewarding part: tracking a specific, valuable action that a user takes on the website. This is where measurement moves beyond basic page views and starts quantifying what truly drives the business forward.

Checking the Status in Google Ads

After verifying everything with Preview Mode and clicking the “Submit” button in GTM to publish the changes, the final check is back in Google Ads. It is important to be patient; it can take a few hours, or sometimes up to 24 hours, for Google Ads to process the data and update the status of the conversion action.

The status can be found by navigating to Goals > Conversions > Summary and looking at the “Tracking status” column for the conversion action created. The following is a guide to interpreting these statuses to avoid unnecessary panic.

• Unverified: This means Google has not seen the tag fire yet. This is completely normal right after setup. If it stays this way for more than 24 hours after a known conversion has occurred (one can be triggered by clicking an ad and converting), it is a sign to go back and re-check the setup in GTM Preview Mode.
• No recent conversions: This status is a common source of anxiety, but it is actually good news regarding the technical setup. It means Google has successfully detected and verified the conversion tag, but there have been no conversions attributed to a Google Ad click in the last 7 days. The tracking is working correctly. This status is a signal to look at campaign performance (e.g., ad copy, landing pages, targeting), not a sign of a technical problem with the tracking implementation. Mistaking this for a technical error is a frequent pitfall that leads to unnecessary troubleshooting.
• Recording conversions: This is the goal! This status means the tag is working, and Google has successfully tracked conversions from ads within the last 7 days. Valuable data is now being collected to optimise campaigns.

Next Steps: From Tracking to Growth

Implementing conversion tracking is not the finish line; it is the starting line. With a reliable stream of data now established, the focus can shift to enhancing that data and using it to drive more sophisticated marketing strategies. Here is a clear, actionable roadmap for what to do next.

• Explore Enhanced Conversions: Now that basic tracking is working, the next logical step is to improve its accuracy. Work with a developer or use GTM’s built-in features to fully implement Enhanced Conversions. By passing hashed, first-party data, more conversions can be recovered that would otherwise be lost to browser privacy settings, leading to a more complete dataset and smarter bidding.
• Set Up Dynamic Remarketing: With the Google Tag now firing on every page, the foundation for powerful remarketing audiences is in place. The next level is Dynamic Remarketing, a highly effective tactic, especially for e-commerce. This allows for showing ads to past visitors that feature the specific products they viewed, added to their cart, or purchased. This requires connecting a product feed to Google Ads and adding custom parameters to the Google Tag, but it can deliver a significantly higher return on investment.
• Deepen Your Analysis with Google Analytics 4: To gain a truly holistic view of the customer journey, link the Google Ads and Google Analytics 4 (GA4) accounts. This integration unlocks two powerful capabilities. First, sophisticated audiences can be built in GA4 (e.g., “users who watched 75% of a video and visited a pricing page”) and then imported into Google Ads for highly targeted remarketing campaigns. Second, the full, cross-channel user journey can be analysed in GA4’s reports to answer complex behavioral questions that Google Ads alone cannot, such as how organic search and paid social interactions contribute to an eventual Google Ads conversion.
• Review Your Attribution Model: At the beginning of this process, the advice was to stick with the default “Data-driven” attribution model. Now, with a steady stream of reliable conversion data, it is the perfect time to revisit this setting more meaningfully. Explore the different models available in Google Ads (e.g., Last Click, First Click, Linear) and use the Model Comparison report to understand how each model would re-distribute conversion credit across campaigns. This can provide a more nuanced understanding of how various touchpoints contribute to the final conversion.
• Schedule Regular Audits: The threat of “tracking degradation” is real. A website update or a plugin change can inadvertently break a perfectly good setup. To prevent this, formalise the monthly health check mentioned in the conclusion. Create a recurring calendar event, for example, for the first Monday of every month, to spend 15 minutes checking the tracking status in Google Ads and running a quick test in GTM’s Preview Mode. This simple, proactive habit ensures the data pipeline remains healthy and trustworthy over the long term.

Conclusion: You’ve Built a Foundation for Growth

Congratulations! A journey through one of the most challenging, and most valuable, tasks in digital marketing has been successfully navigated. Take a moment to appreciate what has been built. The days of “flying blind” are over. There is now a trustworthy system that provides the data needed to stop wasting money, optimise campaigns with confidence, and prove the ROI of marketing efforts to any team, boss, or client.

This is a powerful foundation. However, the digital world is always changing. The website will be updated, and platforms will evolve. This can sometimes lead to “tracking degradation,” where a setup that once worked perfectly can silently break over time. To stay ahead, it is a good practice to check the conversion status in Google Ads once a month. This quick health check can prevent weeks of lost data and ensure that the powerful system just built continues to serve as a reliable guide for growth.

Frequently Asked Questions