Analytics9 min
When GA4 shows half the purchases: a tracking audit in an online store
Ads are running, orders arrive, and none of the reports agree. In this store Meta caught about 95 percent of purchases while GA4 caught fewer than half. Below: the three causes we found by measuring, and how to tell them apart in your own store.
In short
- 13 tracking cookies before consent, zero after the fix
- Withdrawal used to delete 1 cookie out of 22
- Consent Mode failed because another plugin rewrote the page
- Server-side sending ran with no consent check at all
- After the fix, attributed orders drop, and that is correct
Where it started: ads work, reports disagree
A mid-sized WooCommerce store. Ads run on several platforms, orders come in, and the reports do not agree with each other. Meta shows almost every purchase, Analytics fewer than half, and the store admin a third number.
Before changing anything we measured the current state and wrote it down as the baseline. Without it there is no way to say whether a week of work made things better. Measurements were taken in a clean browser session and repeated the same way after every change.
Why Consent Mode failed in both directions
Google Consent Mode was enabled and still never activated. The cause was in another plugin: it opens an output buffer and rewrites the whole page HTML, renaming the data layer. The consent calls ended up in the rewritten copy, which Google does not read.
This is a good illustration of why an audit has to be measured rather than read out of the settings. In the settings everything looked correct. In the browser the consent signal never reached its destination, before consent or after it.
The hardest finding: a send that leaves no trace in the browser
A conversions API was live on the server side. Every order went straight to the ad platform with a hashed email, phone, name and date of birth attached, and no consent check stopped that path. A send like this leaves no trace in the browser, so neither the browser tools nor an audit read from HTML will find it.
That is why it was the first thing we fixed, before touching the banner or the documents. A filter reads the consent record stored on the order and sends only when consent was given. We verified it in both directions with real orders: a consenting visitor's purchase reaches the platform, a refusing visitor's does not.
What else we fixed, and what it changed in the reports
In the Tag Manager container we found seven dead Universal Analytics tags and two tags sending the visitor's email and IP as ordinary parameters, although nothing ever filled them. A second website was mixing its traffic into the same Analytics property through the shared container. We cleaned the container and separated the other site.
On the Meta side two pixels were running, and the one collecting data was the one not used for advertising. We kept one. Worth knowing upfront: after work like this the number of attributed orders in the reports goes down, because some of them had been attributed without consent. That is the correct number, not a regression.
How to check your own store
The first test takes a minute: a private window, browser tools, the Application tab, and count the cookies before touching the banner. Zero is the only correct answer. The second test: accept, withdraw, and count again.
The third needs one real order: place it and count how many purchase events reached each system and whether the amounts match. If two showed up anywhere, the reports flatter you until somebody starts allocating an ad budget on them. Audit €200, get in touch.
Five signs your reports are lying
Answer for your own website. “Not sure” counts as a risk: what you don't know, nobody is checking.
Answer, and your result appears here.
Order an audit, €200Related services
Services related to this topic.
- Analytics and ad trackingGA4, Google Tag Manager, Meta Pixel with the Conversions API, and ChatGPT Ads. Tracking that counts one purchase once, and only with consent. Quoted from the audit findings + VAT.
- GDPR and cookie consentA cookie banner that actually blocks: zero cookies before consent, withdrawal that deletes, and documents written against the real configuration. Quoted from the audit findings + VAT.
- WooCommerce online storesCustom-built WooCommerce stores with LT payments and parcel lockers. From €2,500 + VAT.
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