A Simple Guide to Redirects for SEO. 301, 302, etc.
Here at The Status Bureau, we are often asked about redirects – and bring them up to our clients all the time. They’re a way of telling a user’s browser that the page has moved, such as in the instance of a redesign.
Example: the page http://example.org/contact.php has now move to the page http://example.org/contact-us.php
There are five different URL redirects that you can use; 301, 302, 303, 307, and 308. The numbers are the server’s status codes and how each redirect is treated. The TLDR version of this post is to always use 301 redirects.
Use this one. The way SEOs used to refer to the value of using this type of redirect is that it would pass the most link juice or Pagerank. Those are both outdated terms now, but the sentiment is the same. You’re going to want Google to completely trust the forward and the new page as much as they should the original or old page.
You can implement 301 redirects by writing a few lines of code on your .htaccess file (examples of that here). Getting to your .htaccess file will require FTP access. WordPress sites owners can use Yoast’s premium plugin or install a free plugin like the Simple 301 Redirects plugin.
Found / Temporary redirect.
This is an overly common type of redirect which is not recommended by any SEOs. The fundamental reason is that when the Google crawler sees a temporary redirect, it doesn’t entirely trust the forwarding domain like in the case of a 301 redirect.
Google’s John Mueller once stated that 302 redirects are fine and that Google recognizes them, but it has always been the stance of reputable SEOs to use 301 redirects no matter what. We recommend to avoid 302 redirects.
303 and 307 redirects were updates to the common 302. If a browser doesn’t understand a 303, a 302 can be used.
Not Modified Redirect.
A 304 redirect is a Not Modified status and is rare. It’s a redirection to a previously cached result. We don’t recommend using this unless you absolutely know what you’re doing and why.
Found / Temporary Redirect.
A 308 is very similar to the 301 redirect and can be used in the same way to preserve the SEO quality of the redirect. It’s less common than a 301 redirect and the difference is that a 301 may incorrectly be changed to a GET method, whereas a 308 cannot. If you don’t know what that means or don’t care, stick with the 301.
For a thrilling read on redirects, here’s the Internet Engineering Task Force’s Internet standards track protocol on redirects. https://tools.ietf.org/html/rfc2616#section-10.3