“How long should I keep my 301 redirects?”
That’s a recurring question--that is, Google is often asked that question.
Google, via its Search Central YouTube channel, often publishes content. One series of their videos is called AskGooglebot, and it’s a series of short Q&A videos.
The title of one such video (which, as I type this, was released within a day ago) is the titular question of this post.
Google’s John Mueller often hosts these.
Here’s part of what he said, in relation to this question:
“Our recommendation for site moves is to use 301 permanent redirects.
“...How long is permanent when it comes to redirects? At Google, we try to reprocess all pages at least every few months. Most pages are checked much more often.
“However, the amount of crawling is limited, and there are many, many pages that we'd like to crawl, so we have to prioritize. When a URL changes, our systems need to see the change in the form of a redirect for at least a few times in order to record that change.
“To be certain that a redirect has been seen a few times, we recommend keeping the redirect in place for at least one year. It's also important to update all references to the old URL.
“That includes links the page may have within your website and critical links from outside of the website.
“...It's always fine to keep a redirect longer. But you should aim for at least one year.”
So, there you have it.
Believe it or not, as resourceful as Google is, it does have crawl limits, so Google can’t always crawl every single page of every single site every single time.
That’s why, when it comes to how long a 301 redirect should be kept, a year is a good amount of time.