In short. Use session-source reporting with purchase key events and purchase revenue, then examine event-level attribution for sales paths spanning visits.
Definition: Measuring sales after AI referral visits means connecting recorded purchases to visits attributed to AI assistants. A session groups interactions during a visit, and a key event records an action considered important to the business.
Key facts
- As of 17 October 2026, Google's Traffic acquisition documentation describes session-level reporting for both new and returning visitors.
- Google's key event documentation explains that the Key events column can be narrowed to a specific event through its All events menu.
- Google's default channel definitions include an AI Assistant channel that excludes Google's AI Overviews and AI Mode.
- Google's traffic-source scopes documentation distinguishes session-source reporting from event-level attribution, which distributes credit for key events.
How are purchases recorded?
Google's Measure ecommerce guide specifies a purchase event with an items array describing the purchased products. Its example includes transaction_id, value and currency. These fields connect the event to a transaction and its monetary amount.
Google's metrics reference identifies purchase as a key event by default. For sales reporting, purchase provides the recorded outcome; a form submission can be tracked as a separate outcome.
Which visits belong to AI assistants?
Google's Traffic acquisition instructions give this report path:
Reports > Acquisition > Traffic acquisition
The Session source / medium dimension identifies the source and medium associated with a session. Selecting this dimension and searching the table for an assistant source present in the property provides a source-specific view.
Google's default channel documentation also provides an AI Assistant category under Session default channel group. When the referrer matches Google's assistant list, the medium becomes ai-assistant and the campaign becomes (ai-assistant). These labels provide another way to group recognized assistant visits. The channel excludes AI Overviews and AI Mode, so its totals cover a defined subset of AI search traffic.
Which sales metrics should be compared?
Google's key event guide explains how to select a particular key event in reports and build explorations using compatible dimensions. Selecting purchase keeps the count focused on purchases when other actions are also marked as key events.
Google's Traffic acquisition report defines Session key event rate as sessions containing a key event divided by total sessions. A purchase-specific rate therefore measures the share of sessions containing a purchase. The Key events count measures occurrences, so repeated purchases within a session affect the count differently from the session rate.
For monetary reporting, Google's metrics reference defines Purchase revenue as purchase revenue after refunded transaction revenue. An exploration can pair this metric with session-source dimensions. Total revenue has a broader scope that includes advertising revenue, according to the Traffic acquisition documentation.
What happens when the sale comes in a later visit?
Google's scope documentation assigns new session-source values when users return. First user source records the acquisition source of the user's initial session. Choosing between these dimensions changes which question the report answers.
For a purchase path spanning visits, the same documentation describes event-scoped Source and Medium dimensions. These use the property's selected attribution model to distribute credit. Changes to that model leave session-scoped dimensions unaffected. A sales report should identify whether it reports purchases within assistant-attributed sessions or attribution credit across the purchase path.
Related terms
FAQ
How can I check that purchase tracking works?
You can use Google's ecommerce validation instructions to inspect events and their parameters in DebugView. Open the purchase event to check its transaction data; the documentation also explains how repeated transaction IDs can suppress repeated test events.
Can I measure enquiries alongside purchases?
Yes. Google's key event documentation allows any collected event to be marked as a key event. You can report an enquiry event separately and select purchase when measuring completed sales.
Sources
- Google, "[GA4] Traffic acquisition report", accessed 17 October 2026
- Google, "About key events", accessed 17 October 2026
- Google, "Default channel group", accessed 17 October 2026
- Google, "Scopes of traffic-source dimensions", accessed 17 October 2026
- Google, "Measure ecommerce", accessed 17 October 2026
- Google, "API dimensions and metrics", accessed 17 October 2026
- Google, "Validate your ecommerce setup (gtag.js)", accessed 17 October 2026
Check how a page reads to answer engines. Open the GEO score analyzer