Cross Domain Tracking

Because the booking engine runs on a different domain (live.high-level-software.com) to your hotel website, GA4 treats these as separate sessions by default, which breaks the end-to-end journey. Cross domain tracking fixes this, stitching both domains together so GA4 recognises the guest's full path from your website through to booking completion.

Setup

Step 1 - Configure GA4

Follow these steps to configure GA4:

1. Click Configure Tag Settings | Configure Your Domains

2. Add both domains:

   • Your hotel website

     and

   • high-level-software.com

3. Click Save

Step 2 - Add Ads Conversion Linker (if running Google Ads)

In GTM, create an Ads Conversion Linker tag and add both your hotel domain and high-level-software.com to the domain list. Set the trigger to fire on all pages across both domains.

Step 3 - Keep the original traffic source across the domain jump

Adding both domains in Step A is only half the job. GA4 also has to carry the visitor’s identity - and with it their original source (Organic, Paid, Direct, etc.) - across the jump from your hotel website to the booking engine. It does this by adding a linker parameter (_gl=…) to the booking link at the moment the guest clicks it. If that parameter does not travel with the guest, GA4 starts a brand-new session on the booking domain and records the booking as a referral from high-level-software.com instead of the source that originally brought the guest to your site.

For the linker to work, all of the following must be true:

• The same GA4 property and Measurement ID (G-XXXXXXXXXX) is used on both your hotel website and the booking engine. Cross-domain stitching only works within a single property — two different IDs can never be joined.
• Both domains are listed under Configure your domains (Step A) — including every hotel or venue website that links into the booking engine, not just your main site.
• The ‘Book Now’ link is a standard clickable link (an <a href> pointing at high-level-software.com) that is present when the page loads. GA4 automatically adds _gl to links like these.
• The link does NOT pass through a redirect, button script or pop-up that drops the query string. A JavaScript redirect, a form submit, a link-shortener, or a ‘book’ vanity domain that forwards to the booking engine will all strip _gl and break attribution.
• Analytics consent is granted (see the note below) without it the visitor’s ID may not persist across the two domains.

Step 4 - Exclude the booking domain as a referral

As a safeguard, tell GA4 never to treat the booking engine as a traffic source.

1. Click Configure Tag Settings

2. List Unwanted Referrals - Add high-level-software.com

   This stops the booking domain being logged as a referral in the rare event that a session does restart

How to diagnose a cross-domain attribution problem

If bookings are still being credited to the wrong source, run a live test booking with GTM Preview and GA4 DebugView both open, and check the following in order:

• On your website, click the ‘Book Now’ link and confirm the destination URL gains a _gl=… parameter (Step 3)

• In DebugView, confirm the booking-engine session shows the same client ID as the website session — not a brand-new one

• On the confirmation page, open the purchase event in DebugView and read session_source / session_medium. This is the true attribution - judge success here, not in the standard reports

• Confirm the Measurement ID firing on the booking engine matches the one on your website