As you’ll know, Google has recently been putting more emphasis than before on securing your site via HTTPS, or Secure Socket Layer (SSL) technology. This is a form of encryption that helps protect your website against certain types of attack, and helps prevent website communication (the transfer of data) from being intercepted.
This is especially important if you’re using an e-commerce site, or if your site is collecting sensitive or personally identifiable information from its users.
As such in fact, Google has recently enacted a requirement for sites that receive traffic via paid search marketing (Google Ads) to be HTTPS sites, and having an SSL certificate (being https in other words) has already been a minor SEO ranking factor for some time.
Now, in a recent Google Webmaster Hangout, John Mueller, Google’s Senior Webmaster Trends Analyst, has revealed that Google strongly recommends using 301 redirects on a URL by URL basis to make the transition smoother in terms of SEO.
301 Redirects
A 301 redirect is an instruction written into a websites .htaccess file, which tells Google that the page which previous resided at that URL has permanently moved to a different URL, and provides the new URL.
This makes it easier, faster and more likely that any SEO value of the page will be passed to the new destination.
According to John Mueller, “We strongly recommend use clean 301 redirect from on a per URL basis for HTTP migrations.” If you do not, they might “have to reconsider and think, well are they doing something unique here that’s not just a generic site move” and that can make “these moves take a lot longer and makes it a lot harder,” he added.
Best Practice
Although using 301 redirects for site migrations has always been best practice, this is certainly the clearest indication from Google in an official platform that failing to use 301 redirects can have a negative impact on migrating your site to HTTPS.