For years, marketers have relied on cookie-based tracking and client-side analytics to measure campaign performance. But with rising privacy regulations (GDPR, CCPA), browser restrictions (Safari ITP, Firefox ETP), and ad blockers, traditional tracking is more and more unreliable.

The biggest issues with client-side tracking today:
🚫 Cookie lifespan shrinking – Safari limits cookies to 7 days (or less)
🚫 Data loss due to ad blockers – Up to 30% of users block tracking scripts entirely.
🚫 Discrepancies across platforms – Facebook, Google, and GA4 may all report different numbers.

The solution? Server-side tracking and first-party data strategies.

What Is Server-Side Tracking, and Why Does It Matter?

Diagram courtesy of Google.

Server-side tracking moves data collection from the browser (client-side) to your server, giving businesses more control over their analytics.

How it works? Instead of relying on JavaScript pixels, events are sent to a first-party server before being forwarded to analytics and advertising platforms (GA4, Facebook, LinkedIn, etc.).

Key Benefits:
✅ Improved data accuracy – Reduces discrepancies between platforms.
✅ Bypasses ad blockers – Since data is sent from your server, it’s harder for blockers to detect.
✅ Better privacy compliance – Allows more control over user data storage and consent.

Setting Up Server-Side GTM for GA4

Implementing Server-Side Google Tag Manager (ssGTM) for GA4 provides greater control over tracking accuracy and data enrichment. Here’s a simplified step by step:

1️⃣ Setting Up a Server-Side GTM Container

1. Go to Google Tag Manager and create a new server container.
2. Deploy the container using Google Cloud App Engine or your preferred cloud service.
3. Configure the domain to a first-party subdomain (e.g., analytics.yourdomain.com) to prevent cookie restrictions.
4. Enable logging and debugging to verify request flows.

2️⃣ Sending Data from the Browser to ssGTM

1. Modify your GA4 configuration tag in GTM to send hits to the server-side endpoint instead of directly to Google Analytics.
2. Adjust cookies to be set in a first-party context and server-side, avoiding expiration issues caused by Safari ITP.
3. Implement event forwarding rules to enrich data before sending it to GA4, Facebook, or other tools.

3️⃣ Configuring GA4 as a Data Collection Pipeline

GA4 should be viewed as a data collection hub rather than just an analytics interface. The most effective way to leverage GA4 is by using it as a pipeline to feed BigQuery and other first-party storage solutions, ensuring full data ownership and analysis flexibility.

Why is this important?

✅Avoid reliance on GA4’s reporting UI, which is limited in various ways and long-term data retention.
✅Enable advanced ML models by processing granular event data in BigQuery.
✅Experiment with attribution modeling beyond GA4’s built-in options, allowing for better cross-channel measurement.

Future-Proofing Analytics for the Next Decade

With privacy laws tightening and AI-driven attribution models evolving, the future of analytics is about data ownership and adaptability. Businesses that invest in server-side tracking, clean data pipelines, and event-based analytics today will have a competitive edge tomorrow.

Me and my team at VertoDigital, help brands implement GA4, server-side GTM, and AI-driven measurement strategies to future-proof their marketing analytics. Want to optimize your tracking setup? Give us a shout.