Consent banners create up to a 40% traffic gap
GA4 only tracks visitors who give consent. That means part of your traffic isn't reflected in your reports.
In the EU, most websites operate behind a consent banner. When a visitor clicks "Reject":
- No pageviews.
- No sessions.
- No attributions.
In addition, ad-blockers remove additional visits before GA4 even loads.
The result: part of your traffic is structurally invisible.
Those missing visits distort dashboards, attribution models, and performance reviews.
The fix: Not replacing GA4, but adding a cookieless traffic baseline alongside it so you can see the full picture.
Case Study
GA4
1.6M
Actual traffic
2.03M
Missing traffic
400K+
(+20%)
Hebban, a Dutch media company, measured over 400,000 pageviews that never appeared in GA4.
Run a side-by-side test on your client's data
A real example
We ran this side-by-side with Hebban, a Dutch media company. GA4 captured behavioural data after consent, while Simple Analytics measured total traffic in parallel, independently of consent.
Case study
Hebban.nl: 400,000+ missing pageviews
GA4
1.6M
Actual
2.03M
Missing
400K+
(+20%)
Over 400,000 visits never appeared in GA4. Consent banners and ad blockers prevented tracking, so this traffic was never collected.
Read the full case study →How the additional layer works
Simple Analytics is a privacy-first analytics tool that does not use cookies, trackers, or personal data. Because no personal data is processed, consent is not required to measure pageviews while remaining GDPR-compliant.
GA4 remains responsible for behavioural depth and attribution. Simple Analytics provides a complete traffic baseline.
Together, they give you the full picture.
Why this matters for agencies
If you manage clients:
- Total traffic is underreported
- Campaign performance may be inaccurate
- Attribution may lack full context
A 20% difference changes how results are interpreted.
Running a parallel baseline gives you:
- Clear separation between consented and total traffic
- More defensible reporting
- Fewer "traffic dropped after CMP change" conversations
Complement, don't replace.
Run it on one client
- 01
Install Simple Analytics next to GA4.
- 02
Run both for 30 days.
- 03
Compare totals.
There is no migration required. No CMP changes. GA4 stays in place.
Setup takes minutes. And it won't slow down your website.
See the gap for yourself
If you work with clients and want to quantify the consent gap, start with one domain and run a side-by-side comparison.
Book a short setup call and we'll configure it together.