Mastering cross-domain tracking: connect your event website with your ticketing provider (GA4)

When you're running events, knowing where your ticket sales come from is key to optimising your marketing spend. But what happens when your website and your ticketing platform are on two different domains? Without proper setup, you could be flying blind—missing out on crucial data about what's driving conversions.

That’s where cross-domain tracking comes in.

What is cross-domain tracking?

Cross-domain tracking allows you to follow a user as they move from one domain to another—say, from youreventsite.com to ticketprovider.com—without losing their session or campaign information. It essentially "connects the dots", so that Google Analytics (or your platform of choice) knows that the person who clicked a Facebook ad, browsed your site, and then bought a ticket is the same person.

Why you need it

If you're using a third-party ticketing provider, your users are often redirected off your main site to complete their purchase. Without cross-domain tracking, this jump to another domain creates a new session, and the referral source might show up incorrectly (e.g. as "referral" from the ticketing provider) or even be lost entirely.

Result? Your conversion data is fragmented. You can’t accurately attribute which campaigns, ads, or traffic sources are driving ticket sales.

How it works

At a high level, cross-domain tracking works by passing the client ID (or session info) from one domain to the other, typically via URL parameters. When set up correctly, your analytics tool can stitch these sessions together.

If you're using Google Analytics 4 (GA4), here’s a quick overview of what needs to happen:

1. Ensure both domains are added to your GA4 stream's list of "domains" under Data streams > Web > Configure tag settings > Configure your domains.
2. Enable cross-domain linking using either:
   
   
   • Google Tag Manager (GTM): Use the GA4 configuration tag and add the ticketing domain under “Fields to set” using linker settings.
   • gTag.js (Global Site Tag): Use the linker parameter in the config to specify linked domains.
3. Test the setup using tools like Google Tag Assistant or real-time GA4 data to confirm that sessions persist across domains.

Tip: Your ticketing provider must support cross-domain tracking. If they don't allow linking or passing query parameters like _gl, you'll need to work with them or find a workaround, such as server-side tagging.

Real-world example

Let’s say you run cityjazzfestival.com and sell tickets through securetickets.com. A visitor clicks your Google Ads campaign, lands on your site, browses artist profiles, and clicks “Buy tickets”. They're redirected to securetickets.com, where they complete their purchase.

Without cross-domain tracking:

• Their session is split.
• The sale shows as “referral” from securetickets.com.

With cross-domain tracking:

• The full journey is preserved.
• You see that the original campaign (e.g. Google Ads) drove the sale.

Final thoughts

Cross-domain tracking is essential if your conversion happens off-site. It ensures you're measuring true performance and not just fragments. While the setup takes a little technical effort, the payoff is worth it—especially when you're investing in ads, influencers, or content to promote your event.

If you're unsure whether your current setup supports this, we would be happy to chat!