How do we track AI referrals in GA4?

Why it matters.

GA4 now has a default channel called AI Assistant, which Google describes as “the channel by which users arrive at your site from sources like ChatGPT, Gemini, Deepseek, Copilot, or Grok” (Google Analytics Help, read 8 November 2026; first reported by Search Engine Journal on 14 May 2026). Google’s AI Overviews and AI Mode are not in it: those visits stay in Organic Search.

Google has not published its full list of AI referrers, so a custom channel group you control is a sensible backup. Standard properties can have two, they apply to reports retroactively, and they need Editor access.

The 10-minute self-check.

In GA4, open Reports, then Acquisition, then Traffic acquisition:

• Set the primary dimension to “Session default channel group”. Is AI Assistant listed?
• Switch to “Session source” and search for chatgpt, perplexity, claude, gemini and copilot.
• Are any of those still sitting in Referral?

Steps.

1. Check the default AI Assistant channel and note its sessions and key events for the last 90 days.
2. Create a custom channel group (Admin, Data display, Channel groups) with an “AI assistants” channel where the source matches a pattern such as chatgpt|openai|perplexity|claude|gemini|copilot|deepseek. Place it above Referral.
3. Build an exploration: AI channel by landing page by key event.
4. Make sure your lead event is marked as a key event once, and that no second event duplicates it.
5. Exclude internal traffic, so your own tests do not count.
6. Annotate every tracking change with its date.

This set-up is the first step of our conversion tracking and analytics work.

What we saw on prolinkage.com.

How to measure it.

• AI sessions: AI Assistant plus custom-channel sessions, monthly.
• AI key events: key events from those sessions, and the rate per session.
• Landing pages: which pages AI visitors arrive on, quarterly. They show what the engines link to.

Related plays.

• Play 37: Should we ask leads how they heard about us and store it in the CRM? (From AI exposure to pipeline)
• Play 40: How do we connect AI-referred leads to closed revenue? (From AI exposure to pipeline)

Sources.

• Google Analytics Help, Default channel group, read 8 November 2026.
• Google Analytics Help, Custom channel groups, read 8 November 2026.
• Search Engine Journal, Google Analytics adds AI Assistant as a default channel group, 14 May 2026.
• Prolinkage change ledger, GA4 fixes (property 399997904), 6 November 2026.