How to track users across products on PostHog

Navigate to Project Settings → Website & App in your PostHog dashboard. Enable Cross-domain tracking and add all your product domains to the Authorized domains list. This ensures PostHog can track users as they move between different product websites.

In each product's PostHog SDK implementation, use the same distinct_id for the same user. Call posthog.identify('user_123') with identical user IDs across all products. Use a shared user identifier like email address, database ID, or UUID that exists across your product ecosystem.

posthog.identify('user@example.com', {
  email: 'user@example.com',
  product_suite: 'enterprise'
})

Define consistent user properties across all products in Data Management → Properties. Create shared properties like user_tier, signup_date, and company_id. Ensure all products send the same property names and value formats when identifying users.

Create events that include a product_name or source_product property to distinguish which product generated each event. In each product, add this context to all events:

posthog.capture('button_clicked', {
  button_name: 'signup',
  product_name: 'product_a',
  page_url: window.location.href
})

When users sign up or log in across different products, use posthog.alias() to connect anonymous sessions with identified users. Call posthog.alias('new_distinct_id') before posthog.identify() to merge user timelines from different products into a single user journey.

In Insights, create funnels that span multiple products by filtering events with product_name properties. Use Cohorts to segment users who have used multiple products. Set up retention analysis to see how users move between products over time.

Go to Persons in your PostHog dashboard to verify user tracking is working correctly. Check individual person profiles to ensure events from all products appear under single user profiles. Look for proper event attribution and consistent user properties across products.