A website migration is a major change in which the addresses of your website change. Think of a new domain, the switch from http to HTTPS, a new URL structure or a move to a different CMS. Google describes the steps in How to move a site with URL changes.
How do you approach it?
- List all old URLs, from your sitemap, your analytics and your CMS.
- Record for each old URL where it will go.
- Set up permanent server-side redirects, such as a 301 redirect, straight to the final destination.
- Return a 404 or 410 for content you are not carrying over.
- Update internal links, canonicals, hreflang and the sitemap to the new addresses.
- Then monitor indexing in Search Console.
For a new domain, you also submit a change of address in Search Console. Google advises keeping redirects in place for at least a year.
What can you expect?
According to Google, it is normal for rankings to fluctuate for a while as Google recrawls the site. For small and medium-sized sites, moving most pages takes a few weeks; larger sites take longer.
Common mistake
Sending all old pages to the homepage. Google advises against it. A second mistake: a noindex from the test environment that stays in place after launch.
At Outseen, migration is part of the quote for a website project. A detailed step-by-step plan is in Redesigning your website without losing search visibility.