Google Tag Manager: Key Update on April 10, 2025

On March 10th 2025, many of us received an email from Google regarding an upcoming update in Google Tag Manager:

This has caused confusions for many people. In this article, we will explain exactly what the update actually means.

Background

Google tag is a single piece of code that you can find in Google Ads, Google Analytics, and other similar Google products. Google Tag is a prerequisite for sending events to Google services, thus it must be loaded on the website (via GTM or gtag.js).

For example:

• If you want to send an event to a GA4 property with the measurement ID G-12345, then you first need to load a Google Tag with the measurement ID G-12345

• If you want to send an Ads conversion for conversion ID AW-12345, then you first need to load a Google Tag with the measurement ID AW-12345

When an event fires and there is no corresponding Google Tag pre-loaded, which can happen in conditions such as:

• You did not set up a corresponding Google Tag in GTM
• You have set up a corresponding Google Tag in GTM, but it fires after the event

GTM will try to fix this for you by automatically loading a Google Tag that corresponds to your event. However, most of the Google Tag's settings (eg. enhanced measurement, user-provided data) will be toggled off by default.

Flow:

Google Tag Manager update on 10th April 2025

To improve data quality, Google will be making a change in the way GTM auto loads the Google Tag for Google Ads and Floodlight tags.

Updated flows:

Next Step

You have two options:

• No action required. GTM will do this automatically to improve data quality.

OR

• Recommended - Manually set up Google Tag(s) in GTM for all your corresponding Google Ads and Floodlight tags, and ensure that the Google Tag(s) are fired first as priority. For example, you may use this GTM event as your firing trigger: Initialization.

That way, you have full control over what happens in GTM and prevent the auto loading behavior which can be difficult to diagnose.