What Is a 301 Redirect and When Should You Use One?

Changing a Page’s URL Slug

If you rename a blog post from /blog/tips-2024/ to /blog/seo-tips/, anyone with the old URL bookmarked or linked will hit a 404 without a redirect. A 301 from the old slug to the new slug preserves every existing link and bookmark while letting search engines update their index cleanly.

Moving to a New Domain

Migrating from one domain to another is one of the highest-stakes SEO operations you can perform. Every URL on the old domain needs a corresponding 301 redirect to its equivalent on the new domain. Without these redirects, you abandon all the authority and backlinks your old domain accumulated. Our website migration guide covers the full redirect mapping process.

Switching from HTTP to HTTPS

When you install an SSL certificate and move from HTTP to HTTPS, every HTTP URL must 301 redirect to its HTTPS counterpart. Google treats HTTP and HTTPS as separate URLs. Without redirects, you split your link equity between two versions of every page on your site.

Consolidating Duplicate Content

If your site has multiple URLs serving the same content (common with trailing slashes, www vs. non-www or parameter-based URLs), 301 redirects consolidate them into a single canonical URL. This tells Google which version to index and concentrates all ranking signals onto one page instead of splitting them.

Deleting a Page That Has Backlinks

When you remove a page from your site, any external links pointing to it become dead ends. If the deleted page has valuable backlinks, redirect it to the most relevant remaining page on your site. This preserves the link equity those backlinks provide rather than letting it evaporate into a 404.

Restructuring Your Site Architecture

Reorganizing your URL structure (moving pages into new folders, changing category hierarchies) requires 301 redirects from every old URL to its new location. Site restructures without proper redirect mapping are one of the most common causes of sudden organic traffic drops.

Apache (.htaccess)

For websites running on Apache servers, add redirect rules to your .htaccess file in the site root:

# Single page redirect
Redirect 301 /old-page/ https://yourdomain.com/new-page/
# Pattern-based redirect using mod_rewrite
RewriteEngine On
RewriteRule ^old-directory/(.*)$ /new-directory/$1 [R=301,L]

The first method handles individual URLs. The second uses mod_rewrite for pattern matching, which is useful when redirecting entire directories or applying rules to groups of URLs.

Nginx

For Nginx servers, add redirect rules to your server block configuration:

# Single page redirect
location = /old-page/ {
    return 301 https://yourdomain.com/new-page/;
}
# Pattern-based redirect
location /old-directory/ {
    rewrite ^/old-directory/(.*)$ /new-directory/$1 permanent;
}

WordPress Plugins

WordPress users can manage redirects through plugins like Redirection or Rank Math’s redirect module. These provide a graphical interface for creating and managing redirects without editing server configuration files. For sites with fewer than a few hundred redirects, plugins are a practical choice.

For large-scale migrations involving thousands of redirects, server-level rules in .htaccess or Nginx are more performant than plugin-based solutions.

Redirect Chains

A redirect chain occurs when URL A redirects to URL B, which redirects to URL C. Each hop adds server response time and consumes crawl budget. Google follows up to 10 hops in a chain, but best practice is keeping every redirect to a single hop. Audit your redirects regularly and flatten any chains you find.

Redirect Loops

A redirect loop occurs when URL A redirects to URL B and URL B redirects back to URL A. The browser cycles between the two URLs until it gives up and displays an error. Loops block both users and search engines from reaching any content. They typically result from conflicting rules in your redirect configuration.

Crawl Budget Considerations

Every redirect consumes a crawl request. On small sites, this is irrelevant. On large sites with thousands of pages, excessive redirects can consume crawl budget that would be better spent on indexing actual content pages. Clean up unnecessary redirects and fix internal links to point directly to final destination URLs.

For a complete technical SEO review that includes redirect analysis, see our technical SEO checklist.

Redirecting Everything to the Homepage

When site owners delete pages, they sometimes redirect all of them to the homepage. Google treats this as a “soft 404” because the homepage does not satisfy the intent of the original page. The link equity is largely lost. Always redirect to the most topically relevant page on your site.

Forgetting to Update Internal Links

After implementing redirects, update your internal links to point directly to the new URLs. Internal links that still point to redirected URLs force unnecessary server hops and slow down page navigation. Run a crawl of your site after any redirect implementation to catch stale internal links.

Not Testing After Implementation

Always verify your redirects work correctly after adding them. Use a browser’s developer tools (Network tab) or an online HTTP header checker to confirm the response code is 301 and the destination URL is correct. A mistyped destination URL can send traffic to a 404 or the wrong page entirely.

Using Redirects When Canonical Tags Suffice

If two URLs serve the same content and you want both to remain accessible, a canonical tag is a better solution than a redirect. Canonical tags tell Google which URL to index without sending users away from the page they requested. Use redirects when you want to physically move the user. Use canonicals when you want to guide the search engine’s indexing decision.