Server-side tagging is a tracking approach in which the browser sends data first to a server the store controls, which processes it and only then forwards it to tools such as GA4 or ad platforms. In the traditional model, each tag in the browser sends data directly to each vendor.
The most common set-up uses a server-side Google Tag Manager container hosted on a subdomain of the store. The container receives events, lets you remove or transform data before it is sent and routes it to each destination, including conversion APIs.
The usual benefits are tighter control over the data shared with third parties, fewer scripts in the browser and greater resilience to some browser restrictions. The costs include server hosting, initial set-up and ongoing maintenance.
Server-side tagging does not remove the need for consent. Data collected for analytics or advertising is still subject to the visitor’s choices, and the container should be configured to respect them, for example by reading the Consent Mode state.