How to Handle SEO During a Website Migration

A migration’s search risk starts with one question: do your URLs change? Google’s site move guide covers moves where they do: HTTP to HTTPS, a new domain or merged domains, and changed URL paths. If only the infrastructure changes, such as a new host, and every URL stays the same, the guide points to separate instructions. For a move with URL changes, the order matters: prepare the new site, map every URL, update the new site’s own references, plan the redirects, start the move, then monitor. In that order, four of the six stages come before the first redirect goes live.

Know which move you’re making

Move	URLs change?	What carries the signals
New host, same URLs	No	The URLs themselves; follow Google's separate guidance for moves without URL changes
HTTP to HTTPS	Yes, the protocol	Redirects from every HTTP URL to its HTTPS version
New domain, or domains merged	Yes, the host	Redirects, plus the Change of Address tool in Search Console
New URL paths	Yes, the paths	Redirects from every old path to its new one

The more URLs change, the more of the site depends on the redirect map being complete. The guide also says it’s fine to move a site in sections, and suggests that large sites, where technically possible, move just a piece first to test the effects on traffic and search indexing.

Prepare the new site

Robots.txt. Set up a robots.txt for the new site whose rules reflect what you want blocked from crawling.
Temporary blocks. If you use noindex rules while building, prepare the list of URLs you’ll remove them from when the move starts.
HTTPS. For a move to HTTPS, get and configure the required TLS certificates on your server.
Search Console. Verify both the old and new sites, including all their variants, such as www and non-www, and HTTP and HTTPS.

Map every URL

List your old URLs, starting with the important ones, and decide where each will redirect. Google’s guide lists the sources to combine, from sitemaps and server logs to the Links report and your CMS. Map each old URL to its closest real counterpart. The guide warns against redirecting many old URLs to one irrelevant destination, such as the home page, because it can confuse users and might be treated as a soft 404.

Update the new site’s own references

Once the mapping exists, the guide lists three jobs before traffic arrives:

Annotations. Each new URL should carry a self-referencing rel="canonical" link tag, and any hreflang annotations should use the new URLs.
Internal links. Change internal links from the old URLs to the new ones, using the mapping to find them.
Lists for launch. Save a sitemap file containing the new URLs, and a list of the sites that link to your old URLs, which you can find in Search Console.

Plan the redirects

The guide recommends server-side permanent redirects from old URLs to new ones. Google’s documentation on redirects says a permanent redirect is a signal that the target should be canonical, while the indexing pipeline doesn’t use a temporary redirect that way. Point each old URL straight at its final destination, not through a chain left by an earlier migration.

Plan how long the redirects stay. Google’s Change of Address help says to maintain them for at least 180 days, and longer if Google Search still sends them traffic.

Start the move

Configure the server to redirect the old URLs to the new ones.
Remove the noindex rules and robots.txt blocks that existed only for the migration. The guide lists forgetting this among the common mistakes.
Submit the sitemap of new URLs. The guide says submitting a sitemap can help make discovery quicker.
For a domain change, file the Change of Address in Search Console once the redirects are live.
Contact the sites linking to your old URLs and ask them to update their links.

Make room for extra crawling

The guide warns that after a migration, Google will crawl your new site more heavily than usual, because crawls of the old site are redirected to the new one in addition to the usual crawling. Make sure the new site’s server has the capacity for it; a server that slows down or throws errors under that load can lead Google to crawl less.

Monitor the move

The guide tells you to expect temporary fluctuation in ranking during a move, and says that for medium-sized websites it can take a few weeks or more for Google to start showing the new URLs, and longer for larger sites. Track, against a baseline taken before the move:

traffic on both the old and new URLs
the Sitemaps report, which shows how many URLs from the new sitemap have been indexed
the Page indexing report for the new URLs
crawl activity on the new site

A dip that levels off as the new URLs appear points to the move settling. A dip that keeps deepening can point at missing redirects, a leftover block, or a section that didn’t move.

Frequently asked questions

Is moving to HTTPS a site move?

Yes. Google’s site move guide lists URL changes from HTTP to HTTPS as one of its examples, so the same order applies: map, redirect permanently, update canonicals and sitemaps, and monitor.

Can I migrate in stages?

Yes. The guide says it’s fine to move a site in sections, and suggests large sites move a piece first to test the effects.

How long should the redirects stay in place?

At least 180 days, and longer if Google Search still sends traffic to them, according to Google’s Change of Address help.