GLOSSARY
301 vs 302 redirect
A 301 redirect tells a browser and a search engine that a page has moved permanently, transferring its ranking signals to the new address. A 302 redirect signals a temporary move, and search engines generally keep indexing the original URL rather than the destination.
Why it matters
Using the wrong one during a site migration is one of the most common causes of lost search rankings. A 301 is what actually carries earned authority from an old URL to its new one; a 302 used for a permanent move leaves that authority stranded on a URL that no longer serves real content. It also affects how quickly a new URL starts ranking: a 301 signals search engines to transfer authority promptly, while a 302 can leave both the old and new URL in a kind of limbo, with neither fully ranking, for weeks. It also matters for analytics continuity: a properly executed 301 typically preserves referral and campaign tracking data more cleanly than a chain of temporary redirects ever does.
What goes wrong when it's handled badly
Migration tools and CMS platforms often default to 302 redirects because they are simpler to implement, and a site moved with the wrong redirect type can see rankings drop for weeks before anyone realises the redirect type, not the migration itself, was the cause. Every URL in a rebuild here is mapped with an explicit 301 for exactly this reason. A concrete example is an ecommerce platform's default 'redirect' feature during a re-platforming, which implements every redirect as a 302 regardless of intent, silently undermining a migration that was otherwise executed carefully. Auditing every redirect's status code explicitly before a migration goes live, rather than trusting a platform's default behaviour, is the specific check that catches this class of mistake. Keeping a written map of every redirect and its type, reviewed before a migration goes live, is what catches a wrongly typed redirect before it costs rankings.