Google Tag Manager setup — now getting duplicate orders in Analytics

View the site source code right now and search for your measurement ID. If you see it both inside the GTM container snippet and as a directly pasted gtag script in the head section, you've found your culprit. As soon as you delete the manual code, tracking goes back to normal.

Have you checked the transaction IDs for the duplicate orders in Analytics? Does the exact same transaction ID show up on both order rows, or is that field blank on one of them? If one is blank and the other has an ID, one is definitely from the legacy hardcoded script and the other is from GTM.

We ran into the exact same double-counting issue last month. Our data was inflated for two weeks and it messed up our ad optimization because the system calculated cost-per-acquisition at half the actual price. Fixing it took 15 minutes, but since we couldn't correct historical data, we had to exclude that entire period from our reports.

inside gtm under the purchase tags advanced settings theres tag firing options. btw make sure to check "once per page" there then at least on a page level it prevents it from firing eevry single time a customer refreshes the page.

Duplicate conversion tracking will also mislead the automated bidding algorithms on your ad platforms. Until the error is resolved, I recommend switching smart bidding strategies to manual control or closely monitoring campaign learning phases to prevent any impact on budget optimization.

We tried setting up conversions ourselves too. On our e-commerce store, we hooked up analytics through both our platform's plugin and GTM. Next thing we knew, we were making 500 Euro a day but the dashboard was showing 1.000 Euro; we were thrilled at first. Reality hit when we checked the bank account. Everything went back to normal once we turned off the tracking code in the plugin.

Don't just focus on duplicate code. If your external payment gateway redirects users to its own hosted page and then sends them back, the session might be splitting upon their return, firing again as if they're a brand-new visitor.

Open the real-time analytics panel and place a test order, you'll immediately see how many purchase events fire from a single order.

I'd appreciate it if you shared the outcome. Processes without records never improve because you don't know what to fix.

Processes without records never improve, because you don't know what to fix. I'm also curious if anyone does it differently.

I have a question, don't want to go off-topic though. Most time waste accumulates in tasks waiting for approval.

If you post the result here, it will help others too.

There's a common mistake people make when doing this. People defend habits, not processes. Resistance comes from there.

Proven by experience.

Great work. Everyone rushing into google tag manager setup gets stuck at the same point.

The real issue isnt the number, but what its based on.

I have a question don't want to go off-topic though. Solutions that work at a small scale collapse when you grow; I learned this late.

Hope this helps.

you're right. if rankings stay the same but clicks drop the issue isn't your page, but the search result appearance.

correct me if Im wrong.

Let me write how it's done in practice. Ranking is the result, search intent is the input. Look at intent first.

Ranking is the result, search intent is the input. Look at intent first. Hope this helps.

Let me speak from the other side; I'm on the supplier side. Ranking is the result, search intent is the input. Look at intent first.

quick summary for newcomers: Hasty decisions become decisions you have to fix six monts later.

if you get three different answers on a topic, the question was asked wrong.

Quick summary for newcomers: Merge instead of deleting; deleted content doesn't come back.

That's all sorry if I went on too long.