A 404 ("Page Not Found") error means the server returned a "not found" response for a URL. They happen constantly on every website — for mistyped URLs, old bookmarks, links from other sites to pages you've deleted, and bots probing for common file paths. The SEO impact depends entirely on what the 404 URL was.
When 404s Actually Hurt
| Type of 404 | SEO impact |
|---|---|
| A page with external links pointing to it | Link equity is wasted — the links lead nowhere |
| A page that previously ranked for a keyword | Rankings can't transfer to a new URL without a redirect |
| Internal links pointing to a deleted page | Poor user experience; wasted crawl |
When 404s Are Harmless
| Type of 404 | SEO impact |
|---|---|
| A URL that never existed and was never linked to | None |
| Old URLs from a previous site or platform | Usually none, unless they had links |
Probing bots requesting /wp-login.php on a non-WordPress site | None |
| A page you intentionally removed with no replacement | Correct behaviour |
Finding Which 404s Matter
Google Search Console (Coverage report, "Not found" section) shows URLs that have been crawled and returned 404s. More useful is filtering by which ones have external links — Google Search Console's Links report shows this, as do tools like Ahrefs or Semrush.
A 404 with no external links pointing to it is rarely worth acting on.
What to Do About the Ones That Matter
- Page moved to a new URL: add a 301 redirect from the old URL to the new one. See what is a 301 redirect and when to use it.
- Page deleted, no replacement: if there was link equity, redirect to the closest relevant page. If there's genuinely no relevant replacement, a clean 404 is correct — don't redirect everything to the homepage.
- Internal broken links: update them in your CMS or code to point to the correct current URL.
Returning the Right Status Code
If a page is permanently gone, return a real 404 (or 410 "Gone" for more explicit signalling). Never return a 200 status code with a "page not found" message — that's a soft 404 and confuses search engines about the page's validity.
Building a Custom 404 Page
Every site has 404 pages — the question is how helpful they are. A blank default page from the CMS loses the visitor entirely. A well-designed 404 page that offers navigation links, a search bar, or popular pages keeps visitors on the site rather than sending them back to Google. Most CMS platforms let you set a custom 404 template. Include a clear message, the main navigation, and optionally a search field. For the technical side of returning the right HTTP status codes consistently, and for redirecting the 404s that do have SEO value, see what is a 301 redirect and when to use it.
