Google Analytics 4 vs Google Ads conversion tracking

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Following are the main reasons why certain orders/conversions are recorded in GA4 (Google Analytics 4) but not in Google Ads and vice versa:

#1 Flexible conversion counting feature of Google Ads.

Because of the flexible conversion counting feature of Google Ads, there is a possibility that certain transactions that are recorded in GA4 are not recorded and reported by Google Ads.

For example,

If a user clicks on an ad and places two different orders, then Google Ads may report only one order (if the conversion count is set to one), whereas GA4 reports two orders.

#2 The Google Analytics 4 configuration tag did not fire.

If the GA configuration tag did not fire for some reason (maybe it is disabled by an adblocker or a user opted out of tracking), then in that case, GA4 won’t record and report the user’s transaction. However, Google Ads can still count and report such a transaction.

#3 You did not set up both Google Ads and Google Analytics 4 to account for refunds.

You can refund a transaction in both GA4 and Google Ads.

You might see discrepancies if you set up Google Ads to account for refunds, but GA4 does not or vice versa.

#4 Different Conversion Tracking Windows.

GA4 and Google Ads may have different conversion tracking windows. This means that GA4 may record a conversion on a different day than Google Ads.

#5 Delay in transactions being reported in GA4.

There could be a delay in transactions showing up in GA4 compared to Google Ads.

For example, if a user clicks on an ad and completes the purchase, this can show up in Google Ads immediately but could be delayed by up to 72 hours in GA4.

#6 GA4 Data Threshold.

There is a possibility that GA4 data thresholds impact transaction data directly if the data is connected to a small demographic or individual that might be subject to anonymization.

#7 The length of the event name exceeds 40 characters.

If the length of the event name exceeds 40 characters, the event will not be reported as a conversion in GA4.

Such an event may not be imported as a conversion to Google Ads.

#8 Conversion tracking is not set up correctly.

There could be a case where the conversion tracking in Google Ads or GA4 is not set up correctly, or they do not always work because of some ad blockers or privacy extensions.

#9 Cross-device conversions are not tracked in GA4.

Google Ads might track cross-device conversions, which are not tracked in GA4 if Google Signals is disabled.

Google Ads has its own system for tracking cross-device conversions.

On the other hand, GA4’s mechanism for understanding cross-device behaviour is largely dependent on Google Signals.

If Google Signals is disabled in GA4, the platform won’t have access to this cross-device data.

As a result, if you compare conversion data between Google Ads and GA4 with Google Signals disabled, there might be discrepancies, especially regarding cross-device conversions.

Google Ads may report more conversions due to its ability to track these cross-device interactions.

Because of the reasons mentioned above, I have never been a fan of importing conversion data from analytics platforms (whether Universal Analytics or GA4) to Google Ads.

I recommend setting up and using the native conversion tracking from Google Ads.

When you rely on imported conversion data from GA4, there is always a good possibility that the conversions recorded by Google Ads are way lower than those recorded by GA4, even when your Google Ads account is correctly linked to your GA4 property.

#10 GA4 and Google Ads use different attribution models.

If GA4 and Google Ads use different attribution models, then the use of different attribution models alone can create a discrepancy in conversion data between Google Ads and Google Analytics.

With the difference in attribution models, the conversions are not actually lost, but they might be potentially moved outside the date range of comparison between the two platforms.

#11 Difference in Conversion paths.

In GA4, all the Google Ads conversion paths are based only on clicks.

Whereas in Google Ads, the conversion paths can be based on both clicks and impressions.

#12 GA4 and Google Ads can use different attribution times.

Google Analytics defines attribution time as the goal completion or conversion time.

Google Ads defines attribution time as the time of the ad query the user searched for, preceding the click that led to the conversion.

This is because Google Ads usually attributes conversions to the last ad interaction before the conversion occurred, and the ad query is the first ad interaction.

For example, a user comes to your website on 3rd Sept via Google Ads but doesn’t complete any conversion.

Then he visited the website again ten days later on 13th Sept via organic search, and this time, completed a conversion.

In this example, Google Analytics will consider the attribution time as 13th Sep (the time of goal completion), while Google Ads may consider the attribution time as 3rd Sep (the time the user performed the search query).

Google Ads uses interaction time reporting (the date of associated ad clicks), whereas Google Analytics uses conversion time reporting (the date the transaction occurred).

This could lead to discrepancies in sales and other conversions.

The longer the lag time between a click and the final conversion, the larger the discrepancy might be between Google Ads and Google Analytics.

#13 Goal conversion rate is calculated differently between Google Ads and Google Analytics.

Both Google Ads and GA4 measure goal conversion rates, but how each platform defines and calculates it can differ.

The conversion rate in Google Ads is calculated as the number of conversions divided by the total ad interactions that can be tracked to a conversion during the same time period.

The conversion rate in GA4 is calculated as the number of conversions divided by the total number of users (or sessions, depending on how you set it up) during a given time period.

Google Ads allows you to set a conversion window which might be different from the one set in GA4.

#14 Goal conversion counting is different between Google Ads and Google Analytics 4.

In Google Analytics 4, a conversion can be counted only once per event or once per session.

Whereas in Google Ads, a goal completion can be counted many times per ad click.

Even when you export the GA4 conversion data to Google Ads, you will still see some differences in the calculated values because Google Ads performs a different calculation on data than Google Analytics.

Although the underlying data is the same, you may still see differences in the data.

So if a file download is one of your conversions, then GA4 will count only one file download as a conversion in a given session, no matter how many times a user downloads the file in the same session.

Whereas in Google Ads, if file download is one of your goals, then Google Ads can count conversion each time the user downloads the file after an ad click, even in the same session.

In Google Ads conversion tracking, there is no concept of user sessions.

Moreover, GA4 counts conversions from all traffic sources and mediums. Whereas Google Ads count only those conversions which resulted from Google ad clicks/video ad views.

#15 Test transactions in GA4.

Test transactions can all create data discrepancies between Google Ads and GA4 conversion data.

It is common for developers to place test transactions on a website during testing. These transactions are often recorded and reported by GA4 but not by Google Ads.

#16 Invalid conversions in Google Ads.

Conversions in Google Ads might be filtered differently. For example, Google Ads might exclude conversions from certain invalid ad clicks.

This is not the case with Google Analytics. GA4 can still report on the conversions resulting from invalid Google ad clicks.

GA4 may include conversions that Google Ads does not, especially if no filters are applied to exclude internal traffic, bots, or other unwanted interactions.

#17 Google Analytics data sampling issues

Data sampling issues in your GA4 property can easily skew your analytics data and can create a big difference between reported conversion data in Google Analytics and Google Ads.

#18 Conversion data freshness.

Conversions recorded via Google Ads conversion tracking code are updated faster in Google Ads than the conversions imported to your Google Ads account from GA4.

Since most advertisers use and rely on a data-driven attribution model these days, the conversion data between Google Ads and GA4 can be out of sync for up to 24 hours.

You might be operating on incomplete or skewed information if you make marketing decisions based on recent data without accounting for the inherent lag between GA4 and Google Ads.

That’s why I don’t recommend using imported GA4 conversion data in Google Ads.

For more details, check out this article: How to import GA4 Conversions into Google Ads.

#19 Not all Google Ads conversions can be tracked in Google Analytics 4.

GA4 and Google Ads are two distinct platforms, each with its own tracking mechanisms, capabilities, and limitations.

While there’s substantial overlap in what they can track, certain conversion types and situations exclusive to Google Ads might not be seamlessly tracked or mirrored in GA4.

For example, the following Google Ads conversions can not be tracked in GA4 at present:

#1 Cross-account conversions

Cross-account conversion tracking is a feature specific to Google Ads.

It is designed for advertisers who use multiple Google Ads accounts to promote a single website or set of related websites.

Without cross-account conversion tracking, if two separate Google Ads accounts promote the same website and a user clicks ads from both accounts before converting, both accounts might claim credit for the conversion. This could lead to the same conversion being counted twice.

By implementing cross-account conversion tracking, Google Ads ensures that a single conversion is attributed to only one account (based on attribution models and conversion windows), preventing double-counting and ensuring accurate ROI calculations for each account.

GA4 is designed to track user interactions on a website, independent of which Google Ads account drives the traffic.

You could introduce discrepancies if you tried to import conversions from Google Ads without considering the cross-account setup.

This is because GA4 does not inherently recognize the hierarchical relationship of shared conversion actions across multiple Google Ads accounts.

The way Google Ads handles clicks, impressions, and attribution for cross-account conversions might not align with GA4’s data model, especially if different attribution models are applied.

#2 Phone call conversions

Phone call conversions are the conversions that result from phone call extensions or phone numbers embedded on your website.

#3 View-through conversions

These conversions are unique to display and video ads where a user might not click on the ad but might see it and later convert.

Google Ads can track these conversions, whereas GA4 does not have a direct equivalent.

#4 Cross-device conversions (without Google Signals)

Google Ads has a feature that allows for the tracking of cross-device conversions. If a user clicks on an ad on one device and converts on another, Google Ads can track that.

While GA4 offers a similar capability with Google Signals, you won’t see this data in GA4 if you haven’t activated it.

#5 Location-Specific Conversions

When you employ location extensions in Google Ads, you enable additional actions that potential customers can take directly from the ad itself related to your physical store or business location. These actions include:

Get Directions.
Click-to-Call.
Store Visits.

While these conversions can be extremely valuable, especially for businesses with a significant offline or brick-and-mortar component, they aren’t directly trackable in GA4.

#20 User data preferences for tracking methods.

Users may opt out of the analytics tracking option (GDPR rules), which is used to set analytics cookies on the browser and to track session activities.

In this case, Google Analytics will fail to record the conversion, but Google Ads can still track the conversion by using conversion pixel code that is executed at the time of the conversion.

If a user with an ad blocker enabled lands on a website and completes a conversion, the Google Ads conversion pixel might be blocked and thus won’t record the conversion.

However, not all ad blockers block GA4 by default, so GA4 might still capture and report the conversion.

To learn about other differences between Google Analytics and Google Ads data, read the article: Why Google Ads and Google Analytics data don’t match & how to fix it.