HTTP status codes tell search engines how to treat each URL they encounter. Using the wrong status code can waste crawl budget, leak link equity, or cause content to disappear from search results. Getting status codes right is one of the most impactful technical SEO fundamentals.
Status Codes That Matter for SEO
200 OK
The standard success response. Googlebot indexes the content and attributes link equity to the URL. Every page you want indexed must return 200.
301 Moved Permanently
Signals that a URL has permanently moved to a new location. Google transfers approximately 100% of link equity to the destination URL and eventually replaces the old URL in its index:
# Nginx 301 redirect
location /old-page {
return 301 /new-page;
}
Use 301 for domain migrations, URL restructuring, and consolidating duplicate content.
302 Found (Temporary Redirect)
Tells Google the redirect is temporary and the original URL should remain in the index. Google does not transfer link equity as reliably with 302s. Common mistake: using 302 when you mean 301. If the move is permanent, always use 301.
304 Not Modified
Indicates the page has not changed since the last crawl. Googlebot uses If-Modified-Since and If-None-Match headers to check. Returning 304 when content has not changed saves crawl budget and server resources.
404 Not Found
The URL does not exist. Google will eventually remove 404 pages from its index. A few 404s are normal, but large-scale 404 errors (hundreds or thousands) can indicate broken site migrations or structural problems.
410 Gone
Explicitly tells Google the page has been intentionally removed and will not return. Google deindexes 410 pages faster than 404 pages. Use 410 for content you have deliberately deleted:
# Return 410 for permanently removed content
location /discontinued-product {
return 410;
}
500 Internal Server Error
Indicates a server-side failure. If Googlebot encounters 500 errors persistently, it reduces crawl rate and may temporarily deindex affected pages. Monitor 500 errors aggressively -- they are emergencies for SEO.
503 Service Unavailable
Tells Googlebot the server is temporarily down (maintenance, overload). Include a Retry-After header so Googlebot knows when to come back:
HTTP/1.1 503 Service Unavailable
Retry-After: 3600
Use 503 during planned maintenance. Never use 200 with a "down for maintenance" page -- that replaces your real content in the index.
Soft 404s
A soft 404 occurs when a page returns 200 OK but displays "page not found" content. Google detects these and flags them in Search Console. They waste crawl budget because Googlebot keeps recrawling them expecting real content.
Fix soft 404s by returning actual 404 or 410 status codes for missing pages. Check your CMS for empty category pages, expired products, or paginated pages with no results.
Redirect Chains and Loops
A redirect chain is when URL A redirects to B, which redirects to C, which redirects to D. Each hop adds latency and leaks link equity. Google follows up to 10 redirects but recommends a maximum of 1:
# Bad: redirect chain
/old → /temporary → /new → /final (3 hops, equity loss)
# Good: direct redirect
/old → /final (1 hop, maximum equity transfer)
Audit your redirects quarterly. Tools like Screaming Frog identify chains by crawling your site and following each redirect to its final destination.
Crawl Budget Impact
Every URL Googlebot requests consumes crawl budget. Non-200 responses (especially redirect chains, soft 404s, and 500 errors) waste that budget on pages that provide no value. For large sites (100K+ pages), clean status codes directly affect how quickly new and updated content gets indexed.
Monitoring Status Codes
- Search Console Coverage report -- groups pages by indexing status and flags errors
- Server access logs -- filter for Googlebot user agent and monitor status code distribution
- Screaming Frog or Sitebulb -- crawl your site and generate a status code report
- Real-time alerting -- set up alerts for 500 error spikes to catch server issues before they affect indexing