
Traffic attribution is one of the most important features of analytics platforms such as GA4.
However, due to multiple factors including:
There have been some challenges in achieving the most accurate attribution results.
In this article, we will explain:
The attribution challenges faced in GA4 can be grouped into three pillars:
When you perform a search on Google, you will often see that the top links have a "Sponsored" label. For example:
These are considered "Paid Search" as companies pay money for their links to be listed on top. This is also known as Cost per Click (cpc).
When you click on a paid link, Google automatically adds a unique ad identifier (gclid/dclid) to URL parameter of the landing page. For example:
https://www.mywebsite.com would become https://www.mywebsite.com?gclid=xxXXxxxXXxx
On the landing page, GA4 will read this value and automatically convert it into proper traffic source dimensions. For example:
source / medium = google / cpc
Back to the Google search result page, when you scroll farther down, you will see links without the "Sponsored" label. For example:
These are considered "Organic Search". In order for your links to be ranked high, you need to ensure that your website has good SEO. For example, ensure that your website has good content that is relevant to what users are searching for. You do not need to pay extra money for organic ranking.
For organic links, Google does not add any additional URL parameter.
Keep in mind that both link clicks happen on the same source website - www.google.com. That means that, on the landing website, the only indicator that the traffic source is paid or organic is the gclid URL parameter.
To illustrate:
Now here's the issue. Due to privacy regulation, if users do not consent to advertising (eg. ad_user_data flag is denied), the gclid URL parameter (which is unique to a user) cannot be used by Google.
That means, in cases like this, GA4 has no way of telling if the traffic source is Paid or Organic. Since it can only read that the source website is www.google.com, it can only set the traffic source to Organic. This is the reason for: Misattribution of Google Paid campaigns to Organic.
In 2024, Google has implemented several signal-gathering improvements to reduce this issue. However, the main challenge remains - If the auto ad identifier cannot be used, there's no clear indicator to tell if the traffic source is Paid or Organic. Read to find out how Google intend to solve this in 2025.
(not set) value in GA4 can be due to many factors, one of which is when GA4 events are fired before the config command (eg. Google Tag).
For example, if you have a firing sequence like this:
In 2024, Google made a change in that all GA4 events are deferred until after the config command has been run. You should no longer see this (not set) issue resulting from the
less-than-ideal firing sequence. Nevertheless, we always recommend to fire the config command as priority before any other event tags. For example, it is recommended that you fire all Google Tags on GTM Initialization - All Pages event trigger.
It takes time for GA4 to process the vast amount of data. This is especially true when it needs to connect to multiple ad platforms to reconcile the data. While GA4 is processing data, the traffic source dimensions can be temporarily set to empty which is equivalent to Direct channel.
That means, if you look at today or yesterday's data (which could still be processing) in GA4, you could see a higher percentage of Direct traffic source. This is the reason for: Overattribution to Direct.
Read on to learn how Google intend to reduce this confusion in 2025.
Addresses: (A) Misattribution of Google Paid campaigns to Organic
We should all be familiar with:
As of now, when both methods are used, auto tagging takes priority over the manual tagging method.
In 2025, Google will be changing this to a waterfall logic and adding a new tagging method in between:
Google will be launching this in early 2025. Do stay tuned for more official information and the recommendations for manually adding UTM parameters to your landing URLs as a fallback safety net.
Addresses:
Google will be making two changes to the traffic source data in 2025:
Google will also be launching many diagnostic tools in the GA4 UI to improve clarity and to help identify potential tracking issues early. You will start to see these diagnostic messages in 2025.
These includes:
Do stay tuned for more official information to be announced.