In an episode of Ask Googlebot, John Mueller discussed how URL structure changes affect the SEO of a website.
He began by explaining that, while this may sound like a small change, it’s usually not a simple change for search engines.
If you have to somehow change the address of the page URL, then that page has to be forwarded.
If it is not forwarded, it’s going to get lost.
It doesn’t matter how URLs are changed – whether you’re rebuilding a site, or if you’re simply removing a slash at the end of your URLs.
These are all considered site moves on Google’s side.
John referenced this article that will be helpful for any URL changes.
For any URL changes that you may come across, John recommends researching the options available to you, along with their possible effects.
These types of site changes take time and they can also impact ranking.
John also recommends that you consider the timing of when you make these changes.
Next, you want to create a list of old URLs and new URLs – this way, you can cross-reference the changes afterwards.
Then, you can start the migration.
Make sure that you 301 redirect all of the old URLs to the new ones.
You need to update all internal mentions of the URL including links, on forms, within the structured data, within the XML and HTML sitemap files, and the robots.txt file.
Next, you also need to monitor the migration in order to make sure that everything was migrated correctly.
Make sure that all of the pages in question physically have the redirect.
Google Search Console’s report should also show a quick change for the pages that are most important, and then there should be a slower change as Google’s systems process the rest.
Overall, URL changes can take up to several months to complete.
John also recommends that redirects remain in place for at least one year.
John Mueller AskGooglebot Transcript
Today, a question from YouTube is about tweaking a website’s URL structure. Unfortunately, while this may at first sound like a small change within a website, it’s not that simple for search engines. In particular, search engines, like Google, store their index on a per-page basis. So if you change the address or the URL of a page, that page’s data has to be forwarded somehow.
Otherwise, it gets lost. It doesn’t matter if you’re completely rebuilding a website, or if you’re just removing a slash from the end of URLs. These are all essentially site moves. We have extensive documentation that I’ll link to in the description. In particular, we recommend first, research the options and the potential effects.
Since these changes take time and have ranking effects, it’s also recommended to consider the timing of when you make the move. Second, create a list of the old and the new URLs. This will help you to track and check the changes afterwards. Then start the migration. 301 redirect all the old URLs to the new ones.
Also update all internal mentions such as links, forms, structured data, Sitemaps, and the robots.txt file. Finally, monitor their migration. Check all pages for the redirect in Google Search Console’s report. You should see a quick change for the most important pages and then a slower change as our systems reprocess the rest. Overall, this can take several months to complete. Redirects should remain in place for at least one year.