Every page refresh counted as a new session — the 96% bounce rate was 41%

The situation

A childcare center chain with 6 locations in suburban Chicago had just migrated to GA4. Their web developer reported that GA4 showed a 96% bounce rate and average session duration of 8 seconds. The owner was panicking — their website had just been redesigned and cost $18K.

The problem

The GA4 implementation had a critical error: the GTM container included both a GA4 Configuration tag firing on all pages AND a GA4 Event tag for page_view firing on all pages. Additionally, the website used client-side rendering (Next.js) with pushState navigation — each virtual page navigation triggered a new session_start event because the GA4 tag wasn't configured for single-page app tracking.

What we did

1. Identified duplicate GA4 tag firing — removed the redundant GA4 Event page_view tag, keeping only the Configuration tag's built-in page_view
2. Configured GA4 for single-page app tracking using history change trigger in GTM — virtual page navigations no longer trigger new sessions
3. Added scroll depth tracking via GTM scroll trigger (25%, 50%, 75%, 90%) to capture engagement that wasn't reflected in session duration
4. Verified in GA4 DebugView — session continuity maintained across page navigations, bounce rate dropped to 41%

Why it worked

Next.js and other SPA frameworks use client-side routing that doesn't trigger full page loads. GA4 by default fires a new session on each actual page load — in a SPA, this means new sessions only when the user first arrives and on full refreshes. All internal navigation is invisible unless history change triggers are configured. Combined with a duplicate page_view tag, every user action looked like a new 0-second session.