How to add a second website to GA4

When you launch or acquire a second website, GA4 gives you two ways to add it, and the one you pick decides whether the two sites report together or stay separate. Choose deliberately, because changing it later is messy.

First, the decision

It comes down to how you want to report, which rests on the property vs data stream structure:

• Separate reporting: two distinct brands you manage independently, use a new property for the second site.
• Combined reporting: related sites you want to see together, add a new data stream to the existing property.

How to set it up

1. In GA4 Admin, create either a new property or a new web data stream as decided.
2. Install the new stream's tag on the second site, ideally through the same GTM approach you already use.
3. Set up consent on the second site too, a CMP and Consent Mode; a new site is a new consent obligation.

Watch the cross-site traps

If the two sites link to each other and you combined them in one property, set up cross-domain tracking and referral exclusions so a visitor crossing between them is not counted as new each time.

Datahound are analytics and ad-tracking specialists. We fix broken GA4, Google Tag Manager and server-side tracking so every sale, form and call gets counted. Back to datahound.agency · All tracking guides · GA4 property vs data stream