301 Redirect
A 301 redirect tells search engines a URL has permanently moved, passing most of its link authority to the destination and prompting them to update the index.
A 301 redirect is an HTTP status code that tells browsers and search engines a URL has permanently moved to a new address, so they should go there now and update their records accordingly.
What 301 Redirect Means in Marketing
When a URL earns backlinks and ranks in search, it accumulates authority at that address. Changing the URL without a redirect discards that authority: the old address held the equity and the new address starts from nothing.
A 301 redirect preserves the connection. It says the content has moved permanently and that any authority, links and indexing credit associated with the original URL should follow to the new one. Search engines update their index to reflect the new URL and stop indexing the old one.
This makes 301s the standard tool for URL changes you intend to keep. Site migrations, switching from HTTP to HTTPS, cleaning up URL structures, consolidating duplicate pages: all of these rely on 301 redirects to carry SEO equity from the old address to the new one. See the redirect overview for how the HTTP mechanism works.
How 301 Redirect Works
When a browser or crawler requests a URL, the server responds with an HTTP status code. A 301 response includes two things: the status code itself, which tells the requester the move is permanent, and a Location header giving the destination URL. The browser or crawler then requests the destination.
Search engines read the 301 signal and begin the process of updating their index: they transfer the indexing and authority of the original URL to the destination over the following recrawl cycles. The original URL stops appearing in results and the new one takes its place.
The transfer is not instant. Depending on how frequently Google crawls your site, it can take days or weeks before the full authority shows on the destination URL. During that window, rankings can fluctuate.
301 Redirect Example
A retailer restructures its URL format from /products?id=123 to /shop/product-name/. Every old product URL is given a 301 redirect to the corresponding clean URL. Backlinks that pointed to the old format continue to pass authority to the new pages, so rankings are preserved through the migration rather than resetting.
Why 301 Redirect Matters for Marketers
A 301 is how you move content without losing what that content earned. Handled correctly, a redirect preserves rankings through site migrations and URL changes. Handled badly, through missing redirects, long chains or redirects to irrelevant pages, a migration can wipe out months of accumulated authority. Auditing 301s before and after any major site change is a non-negotiable part of technical SEO.
Frequently Asked Questions
How much authority does a 301 redirect pass?
The majority. Google has said a 301 passes close to full link equity to the destination, though some dilution is normal. The transfer is not instant: it takes time for Google to recrawl the original URL, follow the redirect and attribute authority to the new page. Internal links should be updated to point directly to the new URL so crawlers do not consume link budget following unnecessary hops.
When should I use a 301 redirect instead of a 302?
Use a 301 whenever the move is permanent, which covers most situations: page migrations, URL restructuring, HTTP-to-HTTPS upgrades, domain moves and content consolidations. Use a 302 only when the original URL genuinely will return, such as during a short A/B test or a maintenance window. If in doubt, 301 is the right choice, because search engines keep the original URL indexed under a 302, which can split authority and confuse your index.
Does a 301 redirect affect page speed?
Slightly. Each redirect adds a round trip between the browser and the server, which adds latency. A single well-placed 301 is not a meaningful problem, but a redirect chain, where one URL redirects to a second and that redirects to a third, adds up. Browsers and tools like Lighthouse will flag long chains. Audit redirects after major site changes and flatten any chains so every URL reaches its final destination in a single hop.
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