Google doesn't rank "your website" — it ranks specific URLs it has learned to trust over years. A migration that changes those URLs carelessly throws that trust away, and rebuilding it takes months. The good news: rank-preserving migration is a checklist, not a gamble.
Why migrations lose rankings
Three failure modes cover most disasters:
- Changed URLs with no forwarding —
/services.htmlbecomes/what-we-do/and the old address dies as a 404. Every link, bookmark and search result pointing there now hits a wall. - Lost content — pages that quietly brought search traffic get dropped because "nobody looked at them" (nobody internal, that is).
- Technical regressions — the new site is slower, blocks crawlers with a leftover "noindex", or breaks mobile.
The checklist that prevents it
Before touching anything:
- Inventory your URLs — crawl the current site and pull the pages that actually receive search traffic from Search Console. This list is your protected species register.
- Map old to new — every meaningful old URL gets a destination on the new site. One spreadsheet, two columns, no exceptions.
At launch:
- 301 redirects for every mapped URL — the permanent redirect is the official "we moved" notice that transfers link equity. One redirect per URL, not chains.
- Preserve titles and descriptions on pages that perform — rewriting the metadata of your best-ranking page mid-migration is changing the label on a winning product.
- Submit the new sitemap in Search Console the day you launch.
The DNS side (for host moves): lower your DNS cache time (TTL) a day before, migrate, verify on the new host, then repoint — see our DNS guide for why propagation makes rushed cutovers messy. Keep the old host live for a week; it's your instant rollback.
After launch:
- Watch Search Console's coverage report for a spike in 404s — each one is a mapping you missed, fixable in minutes if you're looking.
- Re-run speed tests; a beautiful redesign that's slower than the old site starts the ranking clock backwards.
The realistic expectation
Even a perfect migration can wobble rankings for a couple of weeks while Google re-crawls. A botched one bleeds for months. The difference is entirely in the spreadsheet you made before launch.
Every migration we run ships with the URL map, the redirect table and post-launch monitoring as standard — because "the redesign killed our Google traffic" is the most preventable disaster in this industry.