According to Google’s John Mueller’s Google+ Hangout last Friday, he suggested to keep the 301 redirects live and in place for at least a year after setting them up. He said “I’d aim for at least a year,” when it comes to keeping your 301 redirects in place.
Google takes somewhere between 6-months to an year to fully recognize that a site has moved. Moreover, people might find old links and if those no longer have redirects, they may lead to a 404 page or a parked domain, which would result in a bad user experience.
John addressed the question at the 24:11 mark in the video, “For how many months or years, we should keep 301 redirect rules OR can we remove redirect rules after some time. Will removing the rules have a negative impact? Will Google again start showing old urls in search results as indexed after removing the rules?”
Theoretically, a 301 redirect is a permanent redirect, so you can keep that forever. Practically, it’s not reasonable to keep something like that forever.
In practice, if we recognize this as a permanent redirect, we try to keep that in mind for the future as well. So if you’ve moved your site, and we are able to recognize that within an year or so, then at some point, you can take that redirect down. One must keep in mind that if the 301 redirect is removed, and the links to the old version of the URL exist, then it might show that too.
If you move a site, then certain standard steps should be followed, which also include updating the links to the new version so that the old links don’t end up getting lost. Otherwise, someone might click on the old link and may land on a 404 page or maybe on a parked domain which reflects a bad user experience.
But at the 26:18 mark, almost two minutes later, he got to the point and said:
I’d aim for at least a year [for the 301 to be in place], if possible, I’d try to keep that longer as well, depending on what is reasonable in your situation.
Check out the video here: https://youtu.be/QWL864VlW7I
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