Most migrations that lose rankings lose them for one of four reasons: URLs changed without redirects, redirects were chained or pointed at the homepage, the staging site got indexed, or nobody took a baseline so the damage was invisible for two months. All four are preventable in an afternoon of preparation.
Before you touch anything, take a baseline
A migration is the one project where you genuinely cannot reconstruct the before picture afterward. Once the old site is gone, the old URLs, the old titles, and the old internal links are gone with it, and every argument about what happened becomes unwinnable.
- Crawl the entire existing site and save the list of every URL that returns a 200, with its title and meta description.
- Export twelve months of Search Console query and page data.
- Record which URLs earn impressions and clicks. These are the ones that must survive.
- Save a copy of the current internal link structure, particularly which pages link to your money pages.
- List every external site that links to you, so you can spot which inbound links land on URLs you are about to change.
A spreadsheet with old URL, new URL, and a status column is the entire migration plan. If it does not exist before launch day, the migration is being improvised.
Redirect rules that actually preserve value
A redirect passes almost all of a page's value when it points to a page about the same thing. It passes very little when it points somewhere generic. This is the single most common migration mistake and it is usually done in the name of tidiness.
- Map every old URL to the closest matching new URL, one to one, wherever a match exists.
- Never bulk redirect a section to the homepage. Google treats an irrelevant redirect as a soft 404 and the value evaporates.
- Redirect directly to the final destination. A redirect that hops through two other URLs wastes crawl budget and loses value at every step.
- Keep the redirects in place permanently. Removing them a year later re-breaks every old inbound link.
- If a page genuinely has no equivalent, let it return 410 rather than redirecting it somewhere misleading.
A redirect to an unrelated page is not a redirect. It is a deletion with extra steps.
Keep the staging site out of the index
A staging site that gets indexed creates a duplicate of your entire website, competing with the real one. It happens more often than anyone admits, usually because the block was applied to robots.txt only and the pages were already discovered.
Password protect the staging environment at the server level. That is the only method that reliably works, because it prevents access rather than politely requesting that crawlers stay away. A noindex tag on a page nobody can fetch is not needed.
Then check, after launch, that the staging URLs are not in the index. A site search on the staging domain answers it in seconds.
Launch day, in order
- Push the new site with all redirects already live. Redirects added afterward leave a window where every old URL returns a 404.
- Confirm the new site is not blocking crawlers. A robots.txt disallow carried over from staging is the classic launch day disaster.
- Submit the new sitemap in Search Console and leave the old one in place for a few weeks so Google recrawls the old URLs and finds the redirects.
- Spot check thirty old URLs by hand, chosen from the ones with real traffic, and confirm each lands on the right new page in one hop.
- Verify analytics and call tracking still fire on the new templates.
A temporary dip in impressions for two to four weeks after a migration is expected while Google reprocesses the site. A dip that is still there at eight weeks is a problem, not patience.
What to watch in the weeks after
Check the Search Console coverage report for a spike in 404s, which tells you a set of URLs was missed. Check for a spike in redirects reported as errors, which usually means a chain. Compare your striking distance keywords against the baseline you saved rather than against how you feel.
If traffic to one section collapsed while the rest held, the problem is almost always that section's redirect map, not the migration as a whole. That is a good outcome, because it is narrow and fixable.
How to run a website migration without losing rankings
- Crawl the entire existing site and save the list of every URL that returns a 200, with its title and meta description.
- Export twelve months of Search Console query and page data.
- Record which URLs earn impressions and clicks. These are the ones that must survive.
- Save a copy of the current internal link structure, particularly which pages link to your money pages.
- List every external site that links to you, so you can spot which inbound links land on URLs you are about to change.
Questions people ask
How long does it take to recover rankings after a migration?
With a clean one to one redirect map, most sites see impressions return to the previous level within two to four weeks. Recovery beyond six to eight weeks usually means something structural is wrong rather than that Google is still catching up.
Do I need to redirect if only my design changed?
No. If URLs stay the same, there is nothing to redirect. Design changes carry their own risks around page speed and content removal, but the redirect question only applies when addresses change.
Should I change my URL structure during a migration?
Only if the current structure is genuinely causing a problem. Changing URLs adds the largest single risk in a migration, and tidier addresses are rarely worth it on their own. If you do change them, change them once and map every one.
What about moving from HTTP to HTTPS?
Same rules apply. Every HTTP URL should redirect once to its HTTPS equivalent, and internal links should be updated to point at the HTTPS version directly rather than relying on the redirect.
Will I lose my backlinks?
Not if the redirects are in place and point to relevant pages. Links pointing at old URLs continue to pass value through a permanent redirect. You lose them only when the old URL returns a 404 or redirects somewhere unrelated.
Can I migrate and redesign content at the same time?
You can, but you lose the ability to diagnose. If rankings fall you will not know whether the cause was the move or the rewrite. Separating them by a few weeks makes any problem obvious.
If you are planning a move and want the redirect map checked before launch rather than after, that is exactly what the diagnostic covers.
Founder of Big Brain Digital. More than 15 years across SEO, content operations, ecommerce, and AI search. Based in Boise. More about Chris.