Conversions double-counting after setting up GA4 events, where am I going wrong?

For a quick check, start by turning off the 'form interactions' toggle under GA4 Enhanced Measurement. On most sites running paid ads, that auto-feature ends up firing erratically on random button clicks or abandoned forms anyway and messes up data.

Correction: I misremembered the figure, it was a bit lower.

Enter preview mode in Tag Manager and submit the form. Look at the timeline steps on the left of the summary panel. Click on your triggered tag when the form submits and see if it fired once or twice. If it says two, your trigger condition is catching two DOM events simultaneously.

We had a similar issue last month on a campaign with a 3.500 Euro budget. We had 80 actual sales, but the dashboard showed 162 conversions. Turned out it was due to users bookmarking the thank-you page and revisiting it. We changed the counting method to 'once per session' and the discrepancy between the CRM and analytics dropped to a reasonable level.

this is every marketer's nightmare—you think the ad dashboard looks amazing but the money hitting the register tells a different story. tbh good thing you caught it early; fixing it before the data gets completely messed up will save the ad algorithm too.

you probably have both the direct gtag code and tag manager installed on the site and both might be firing simultaneously on page load check the source code to see if it's called twice

When registration is completed, does it redirect the user to a separate thank-you page, or does an inline green confirmation message just appear where the form was? Did you set it up using a URL rule or a form submission trigger?

Changing the counting method to 'once per session' only masks the symptom, it doesn't fix the root cause. If the tag is double firing or conflicting with enhanced measurement, that unnecessary data bloat continues in the background. You need to find and remove the redundancy directly in the tagging architecture.

edit: fixed a few typos.

The cleanest approach in measurement setup is always a custom data layer event pushed by the developer upon successful form submission. Relying on URL-based or click-based rules constantly leads to these kinds of double-counting issues whenever theme changes happen.

Let me share my experience. A page with low traffic might be reaching the right people. tbh look at where sales come from.

Correct me if Im wrong.

Exactly like that. If you get three different answers on a topic, the question was asked wrong.

Mistakes made on the GA4 event setup side are usually reversible but expensive. Of course, it varies if your situation is different.

Could you elaborate on that? anyway discussing numbers without verifying the measurement setup is a waste of time.

The real issue isnt the number but what its based on. Im also curious if anyone does it differently.

There's also a measurement aspect to this. When we decide without measuring, we always end up in the same place.

Everything goes well for the first three months; problems arise in the fourth.

I agree.

We've heard this a lot, but it never happened like that for us. If you don't write this down from the start, it leads to arguments later.

I'm also curious if anyone does it differently.

Absolutely. If I were to add anything: Just because everyone does it doesn't mean it's right.

Proven by experience.

thanks, that was the answer I was looking for.

I've been dealing with this for a long time. If it's your first time, start small; scaling comes later.

I'd appreciate it if you shared the outcome. Updating an existing page yields faster results than creating a new one.

This is my opinion, I'm not claiming it's absolute truth.