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Subdomain to main domain website migration

March 10, 2022 0 comments

Have you ever wondered about migrating a subdomain to the main domain?

While the migration may make sense from a structural point of view and can also bring a few additional SEO benefits, it is not without potential issues.

In fact, if things go wrong, you may tank your search engine rankings after the migration.

The good news is that you can make this process smoother and relatively risk-free by taking certain steps. Recently, Google’s John Mueller also shared some tips to use when migrating a subdomain to the main domain.

The uncertainty with subdomain migration

According to John Mueller, subdomain migration can be difficult, and it’s also difficult to predict how things will play out after the migration.

“One of the key aspects that is important here when you’re moving from a subdomain to the main domain, to a different directory, for example, is that we need to look at the new website overall and kind of reevaluate the overall situation.

And that means that it’s hard to know ahead of time what exactly will happen,” says John Mueller.

The importance of planning

Mueller also hinted that, for Google, migrating a subdomain to the main domain is different than a 1:1 site migration, because you are “essentially merging different parts of the website.” And it is hard to predict what the final outcome will be.

However, the outcome will depend on your site’s final structure, and that can be improved by meticulous planning.

One important part of planning a migration is mapping the site migration from the old location to the new location.

“What I would recommend doing here is making sure that you have a very clear mapping of your old website to the new one and then really checking all of those old URLs. There are various tools to test that.”

John did not specify any specific tools, but in our experience, Screaming Frog is an excellent tool for help with site mapping during migration.

Once the mapping is done, Mueller recommends double-checking that everything is in order.

“Make sure that everything is moved properly. And then double-check by crawling the main domain again separately to make sure that really, your new website structure is okay and all of the pages can be found.”

The lingering effects of site migration

Once a website — or, in this case, a subdomain — is migrated, it can take a bit of time before things settle down.

John hinted that it could take a couple of weeks until things settle down after the site migration.

The duration of the effects also depends on the number of pages being migrated and the contextual relation of the subdomain content with the main domain content.


Subdomain to main domain migrations can be scary — and there is a lot of things that can potentially go wrong — but you can do it right by following the tips mentioned in this article.

If you have any questions or need any help, feel free to contact us.