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.