Search and SEO
What is 301 redirect?
A 301 redirect permanently sends a request from one URL to another and passes ranking signals to the destination. A 302 signals a temporary move and behaves differently over time. Getting the distinction right is most of what makes a site migration survive.
Also called: permanent redirect · 302 redirect
When to use which
- 301 permanent
- The URL has moved for good. Signals transfer to the destination.
- 302 temporary
- A genuine temporary diversion — an A/B test, a seasonal takeover.
- 308 and 307
- Equivalents that preserve the request method. Relevant for form submissions.
Rules that prevent damage
- One hop only. Chains bleed signal and slow crawling
- Redirect to the closest equivalent page, never en masse to the home page — that is treated as a soft 404
- Keep redirects for at least a year after a migration; removing them at six months undoes the work
- Test the map against a full crawl of the old site, not against a sample
The migration failure this causes
The most common cause of traffic loss after a redesign is not the design. It is a redirect map built from the pages someone remembered rather than from a crawl of every URL that returned 200.
Where this is covered in depth
A definition can only go so far. Migrating a site without losing what it took years to earn covers this properly — 3 minutes, free, no email required.
Who wrote this
Anas Bin Masud builds e-commerce sites and does technical SEO for businesses in the UK, Canada and Pakistan. These definitions come from client work rather than from a content brief — where an entry describes a mistake, it is usually one found on a real site. More about how I work.