What is 301 Redirect?

A 301 redirect permanently sends visitors and search engines from an old URL to a new one, and tells Google to move ranking signals to the new page.

Many website owners change a URL, delete an old page or move to a new domain and assume Google will figure it out. Sometimes it does, slowly. More often, visitors hit an error page and the rankings that page earned over years quietly fade away. A 301 redirect prevents that.

In simple words, a 301 redirect is a permanent change-of-address notice. Anyone who visits the old URL, whether a person or a search engine, is automatically sent to the new one, and search engines understand that the move is permanent.

How it works

The "301" is an HTTP status code that the server sends before any page loads. It means "moved permanently". Google then gradually replaces the old URL with the new one in its index and transfers the ranking signals, including value from backlinks pointing to the old address. Google has said that redirects like these do not lose PageRank, though the new page still needs to be relevant for rankings to hold.

A 302 redirect, by contrast, signals a temporary move. Use it for short-term situations, such as a seasonal offer page, and use a 301 when the change is permanent.

Redirects can be set up in several ways: through your hosting control panel, a WordPress redirect plugin, the URL redirect settings in Shopify, or server rules written by a developer. The method matters less than mapping each old address to the right new one.

When to use a 301 redirect

Moving from HTTP to HTTPS, or from www to non-www.
Changing your domain name, for example after a rebrand.
Renaming URLs to make them cleaner.
Merging two similar articles to fix keyword cannibalization.
Removing a discontinued product that has a close replacement.

An example

For example, imagine an online kitchenware store that redesigns its website. The old URL /products/steel-pressure-cooker-5l becomes /kitchen/pressure-cookers/steel-5-litre/. Without a redirect, people clicking old Google results, saved bookmarks or links from food bloggers all land on a 404 page. With a 301 from each old URL to its matching new URL, customers reach the right product and the page keeps its search history.

Common mistakes

Redirecting everything to the homepage. Google may treat this like a soft 404. Redirect each old page to the most relevant new page.
Redirect chains. Old URL to URL B to URL C slows things down. Point the old URL straight to the final destination.
Redirect loops. Two URLs pointing at each other break the page completely.
Removing redirects too soon. Google suggests keeping them for at least a year after a site move, and longer is safer.

Simple takeaway

A 301 redirect protects the trust your old pages have built. Before any redesign or migration, make a list that maps every old URL to its new home, then update your menus, internal links and canonical tags to use the new addresses directly. It is one of the most valuable parts of technical SEO, and it is much easier to do on launch day than to fix after traffic drops.