301 Redirect

A 301 redirect is an HTTP status code that permanently sends a browser — and a search engine — from an old URL to a new one, passing along most of the original page's SEO value. In a migration, a complete URL-level 301 map (every old address pointing to its new home) is what protects your rankings and stops visitors hitting 404s. Skipping it is the number-one cause of traffic loss when stores move platforms.