The title tag changed itself a half-second after load. Google kept the wrong one.

The title tag changed itself a half-second after load. Google kept the wrong one.

A travel-deals site had perfect server-rendered titles. View source showed them. Yet 60% of their pages ranked under a generic 'Home | TravelCo' title in the SERP. Click-through on those was 1.1%.

I watched the tab title in a slow-throttled load. The correct title appeared, then snapped back to the generic one.

Turns out a hydration mismatch. The server rendered the right , but the client React tree had a stale default in its head-management library. On hydration, React reconciled the head and overwrote the server title with the client's generic value. Googlebot renders with JS — so it executed the overwrite too and indexed the generic title.

The view-source title was correct. The rendered title was not. Two different truths, and Google trusts the rendered one.

We synced the head state so the client produced the identical title the server did. No mismatch, no overwrite.

Across 1,400 pages, correct titles repopulated the SERP over five weeks. Average CTR on those pages went from 1.1% to 3.4%. Organic clicks +180% with zero ranking change — same positions, honest titles.

Hydration doesn't just fail loudly. Sometimes it quietly rewrites your SEO.