Google Ads has begun converting some of its conversion metrics from Universal Analytics 3 to Google Analytics 4 (UA3 to GA4) and it caught some advertisers off guard, despite numerous notices that this will eventually happen.

Ginny Marvin, the Google Ads Liaison, posted about this on X and said, “Some advertisers have noticed our system making changes to GA4 conv actions in their Google Ads accounts. This is the conversion swapping piece of the Setup Assistant migration process with the turndown of Universal Analytics.”

“Ahead of the migration, advertisers that had UA properties linked with their Google Ads accounts were notified of this & the option to opt out of the Setup Assistant configuring certain corresponding conversions and/or audiences in GA4 & applying them in Ads accounts,” Marvin added.

“With the turndown process taking some time, we understand that some advertisers may be caught off guard with these changes being made now and apologize for the confusion. The updates are aimed at mapping UA conv to GA4 conv settings for bidding & avoid duplicate measurement,” Ginny Marvin also said.

Here are those tweets:

Some advertisers have noticed our system making changes to GA4 conv actions in their Google Ads accounts. This is the conversion swapping piece of the Setup Assistant migration process with the turndown of Universal Analytics: https://t.co/a2T2n66OCg 1/3

— AdsLiaison (@adsliaison) September 18, 2023

With the turndown process taking some time, we understand that some advertisers may be caught off guard with these changes being made now and apologize for the confusion. The updates are aimed at mapping UA conv to GA4 conv settings for bidding & avoid duplicate measurement. 3/3

— AdsLiaison (@adsliaison) September 18, 2023

If you have examples of where this caused issues, let Ginny know:

Please report any suspected issues to Support and you may also DM me with details.

— AdsLiaison (@adsliaison) September 18, 2023

Google’s help documents say, “If you import conversions from your Universal Analytics property into Google Ads and use them for bidding, these goals will be switched to the GA4 equivalent. This involves the following steps in your Google Ads account:

• import the equivalent GA4 conversion event
• set its action optimization setting to primary
• set the Universal Analytics conversion’s action optimization setting to secondary.

If you use a Universal Analytics conversion in a Google Ads custom goal, then the Universal Analytics conversion will be removed and replaced with an equivalent GA4 conversion.

There is a lot more detail over here.

Forum discussion at X.