The HTTP status codes that affect SEO, in one table, with what each means for crawling and indexing. Use 301 for permanent redirects (it passes signals), 410 to deindex faster than 404, and 503 for maintenance. Avoid soft 404s (empty pages returning 200) and redirect chains.
The status codes that affect SEO
Every URL returns a status code. These are the ones that change how search engines crawl, index and rank a page.
| Code | Meaning | What it means for SEO |
|---|---|---|
200 | OK | Normal, indexable page |
301 | Moved Permanently | Permanent redirect; passes ranking signals. Use for permanent moves |
302 | Found (temporary) | Keeps the original URL indexed. Use only if the move is truly temporary |
307 | Temporary Redirect | Like 302, HTTP/1.1 strict |
308 | Permanent Redirect | Like 301 but preserves the request method |
304 | Not Modified | Unchanged since last crawl; saves crawl budget |
404 | Not Found | Fine for genuinely missing pages; fix 404s that are linked or valuable |
410 | Gone | Permanently removed; deindexes faster than 404 |
401 / 403 | Unauthorized / Forbidden | Blocks crawling; never on pages you want indexed |
429 | Too Many Requests | Rate-limited; can throttle crawl on large sites |
500 | Internal Server Error | Hurts rankings if persistent; fix urgently |
503 | Service Unavailable | The correct code for maintenance; crawlers back off and retry |
The traps
- 301 vs 302: use 301 for anything permanent, or signals stay with the old URL.
- 404 vs 410: 410 tells engines the page is gone for good and deindexes faster.
- Soft 404: an empty or error page that returns 200. Engines distrust it; return a real 404 or 410.
- Redirect chains: A to B to C wastes crawl budget and dilutes signals; redirect straight to the final URL.
More on redirects in types of redirects and URL redirection.
Frequently asked questions
Should I use a 301 or 302 redirect for SEO?
Use a 301 for any permanent move; it passes ranking signals to the new URL. Use a 302 only when the change is genuinely temporary, because it keeps the original URL indexed.
Does a 404 error hurt SEO?
Not inherently. A 404 for a genuinely missing page is fine and normal. It only hurts when the 404 is an internally linked or valuable page, so fix or redirect those.
What status code should I use for site maintenance?
Return 503 Service Unavailable. It tells crawlers the outage is temporary so they back off and retry without dropping your pages from the index.
What is the difference between 404 and 410?
404 means not found; the engine may keep checking. 410 means gone for good, which signals permanent removal and deindexes the URL faster.
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