GA4 Migration

Migrating to GA4: When to move from Universal Analytics to GA4

Although GA4 has been with us for some time, there are not many who have yet decided to take the step of migrating their data from Universal Analytics to Google’s new measurement system.

Migrating to GA4 is a significant change, moving from a page-viewed and session-based measurement to an event-based one. New KPIs, another way of measuring and metrics that disappear as the, for many essential in their lives, rebound rate. 

On the other hand, it seems that it was yesterday when Universal Analytics stopped being beta, but that was already 8 years ago (April 2014). That time is an eternity for any tool, especially in the world of analytics, constantly agitated by attribution problems, the GDPR, the budding cookieless era…

Google’s notice that in July 2023 the properties of Universal Analytics is already the final blow.  Therefore, the decision should not be whether or not to switch to GA4. There is no choice, you have to do it, because otherwise you will run out of measurement on that date.

Table of Contents

Why does Google want us to move to GA4?

To understand the evolution of Google Analytics we have to go back to 2012, when Google decided that its classic Google Analytics no longer worked because it was excessively based on web technology and did not contemplate the revolution in all aspects that the increasing use of mobile phones supposed.

That’s when he brought out Universal Analytics, which spent a couple of years in beta until becoming standard in 2014. The main difference was that it tried to unify user sessions between web and mobile through a user identifier, which was the first attempt at cross-device measurement (between websites and apps).

But this was not enough, since although sessions could be integrated, the metrics of the apps and the web were very different. Something that Google was already aware of at that time because the same year that Universal came out of beta (2014), Google bought Firebase, an app programming system on which GA4 would be based.

Already in October 2020 Google introduced GA4, in which Google Analytics adopted the firebase measurement model, based on events. These events, in turn, are no longer categorized into category, action and label, but are have a much more flexible categorization system.

Since then there have been improvements: predictive audiencesconversion models, integration with Gogle Ads and Search Console… a statement of intent that Google’s commitment to this measurement system is definitive.

Drawbacks of migrating to GA4

Obviously, not all are advantages. There are some drawbacks of GA4 that we highlight below:

  1. It is incompatible with Universal. It is a totally different measurement system. We are not talking about migrating, as when you gave the migrate button to go from Google Anaytics Classic to Google Analytics. 
  2. It is not easy to understand. Marketing teams, clients, are used to their sessions, their bounce rate… we all have been with the classic Google Analytics metrics for too long and the change is going to be really frustrating for many because of our aversion to change.
  3. New way to report. When you change the metrics, the current reports will change.
  4. It is still in development. Although they have removed the green label, the truth is that there are still aspects in which the tool is noticeable that it is still under construction.

Advantages of GA4

Despite the drawbacks, we can gloss over some of the advantages of GA4.

  1. Measurement with events: There was a time when websites were static, the same for everyone. Currently, there are customization options that allow you to display different versions of the page to users based on their origin. This makes the page views metric no longer make sense, and it does make sense to measure those experiences with events.
  2. Compatible with the existing Google ecosystem (Google Tag Manager, Google Ads, Search console) and the one to come.
  3. Integration with apps: with Universal you could unify sessions on a user id, and that’s fantastic. But now they will be able to unify web and app experiences, since both share the same metrics.
  4. Future-proof without cookies. Since the implementation of the GDPR, rare is the web that does not lose at least 20% of its measurement by users who do not accept cookies. Google intends to replace that void with artificial intelligence, but that will apply in GA4 and not in Universal.
  5. Native connection with Big Query. This is the first step in integrating artificial intelligence into analytics.
  6. Automatic measurement: there are many things that are measured by default, such as outbound links, video views, scrolling, searches, downloads…
  7. It will still be free. As now, only websites with a huge amount of traffic can need the new paid version GA4

Is it time to move to GA4?

Definitely. Yes.

Fortunately, it is not necessary to migrate, but you can have both measurements (Universal and GA4) coexisting and without interfering with each other. That is why you should implement GA4 as soon as possible, so that you have a history at the time you want to make a more advanced implementation, even if you do not have all the possible metrics, if you will have the most basic ones.

As for implementations, if you are considering an advanced implementation of Google Analytics, it may no longer make sense to devote time and resources to Universal Analytics, beyond improvements in measurement and error adjustments. It’s clear that GA4 is going to be the next standard, and that’s where you should bet.

Recommended phases of migration to GA4

The phases do not differ too much from a classical measurement implementation, but we will have to devote more time to training and evangelization, since we start from users with a mental framework already made, and the new measurement will break the schemes.

It is important that although we talk about migration, we are talking about maintaining a measurement in parallel with Universal and GA4.

We could establish the following phases:

  1. Implement basic GA4 measurement now to generate history
  2. 90 days later implement advanced measurement, definition of business objectives and kpis and translation of these objectives into KPIs with GA4 metrics, transfer the metrics and personalized dimensions of Universal to the new measurement.
  3. After completing the implementation, with at least one month of data, train internal marketing teams and customers
  4. Redefine reports. The metrics have changed, and the way we report will have to change.
  5. Start the cycle of recurring improvements in measurement.


As we can see, the decision to make is not whether we will move to GA4 or not, but to do it as soon as possible. Our recommendation, introduce from now on a measurement to generate history and become familiar with the interface and metrics.