A permanent HTTP redirect indicating that a resource has moved. Google treats permanent redirects as a strong canonicalization signal.
A 301 redirect is a server response saying that a resource has moved permanently to another address. The response supplies a destination, and a browser or crawler can request that URL next. It is commonly used when a useful page moves as part of a redesign, URL change or domain migration.
Google treats permanent redirects as strong signals when choosing a canonical URL. That helps explain the role of a redirect, but it is not a promise that all rankings, clicks or commercial results will remain unchanged. The relationship between the old page and its replacement still matters.
A redirect should lead to a useful relevant destination rather than send every retired URL to the homepage. The new page also needs to work. A correct status code does little for a customer if the destination is missing, unrelated or trapped in a chain of further redirects.
Takeaway: Use permanent redirects to maintain the route from an old address to its real replacement. Map important pages individually instead of treating a site migration as one blanket rule.
Example
A consultant moves an existing payroll-service page from /payroll-help/ to /payroll-services/. A 301 can take visitors following the old address to the updated version of that same service. Sending the old address to an unrelated bookkeeping article would not serve the same purpose.
What to check
Check the old URL’s response, the final destination and the destination’s actual content. Update internal links to point directly to the new address. Developers should also consider request-method behavior for forms or application endpoints rather than applying page redirects indiscriminately.
For more detail, see MDN 301 reference.