301 redirect
A 301 redirect is an HTTP response, 301 Moved Permanently, that tells browsers and search engines a page has moved to a new URL for good. Google treats it as a strong signal that the new URL should be the canonical one, and the redirect passes ranking signals such as PageRank to it.
301 vs 302 and other redirects
Google sorts redirects into permanent and temporary. Permanent ones are 301 and 308 responses, instant meta refresh and JavaScript location changes. Temporary ones are 302, 303 and 307 responses and meta refresh with a delay. A permanent redirect tells Google to show the new URL in results; a temporary one keeps the old URL as the likely canonical.
Google recommends a permanent server-side redirect wherever possible, because it is the most likely to be read correctly, and suggests JavaScript redirects only when nothing else is available.
Do 301 redirects lose PageRank?
No. Google's site move guidance says 301 and other permanent redirects don't cause a loss in PageRank. The old URL can still show in results for a while as an alternate name of the new canonical URL.
Good practice for site moves
- Map each old URL to its closest equivalent, not everything to the homepage
- Point straight to the final URL: Googlebot follows up to 10 hops, but Google advises chains of no more than three
- Keep redirects in place for as long as possible, and at least a year
- Update internal links, canonical tags and sitemaps to the new URLs
Example
A firm rebrands from oldname.co.uk to newname.co.uk. It maps every old URL to its matching new one with server-side 301s, updates its own links and XML sitemap, and keeps the old domain's redirects running for well over a year, so links from past press coverage still reach the right pages.
Related terms
Further reading
Our Organic Search service puts this into practice for brands in the UK and US.
