Next.js 15 Error Handling: error.tsx, Server Actions, and Sentry (2026) (opens in new tab)

Proper error handling in Next.js 15 is spread across four different mechanisms that serve different purposes. Most guides cover one of them. This covers all four — and how they work together in a production app. The Four Layers of Error Handling error.tsx — Client component that catches rendering errors in a route segment global-error.tsx — Catches errors in the root layout itself Server action errors — Errors that happen during mutations and form submissions not-found.tsx — Handles 404s from...