A significant website change involving domains, URLs, platforms, hosting, or architecture that requires coordinated search management.
A site migration is a significant change to a website’s platform, location or structure. It can involve a new domain, changed URLs, different hosting or a rebuilt publishing system. The SEO work depends on what actually changes; a hosting move that preserves URLs is not the same project as replacing an entire URL structure.
Start with an inventory of the pages, media and functions the business needs to preserve. If addresses change, map old URLs to relevant new destinations. Also review internal links, canonical annotations, sitemaps and any development-stage crawl or indexing restrictions before launch.
The move should have a verification plan, not merely a launch date. Check important paths and tasks on the new site, retain the evidence needed to diagnose problems and monitor the transition. Search visibility can fluctuate while changes are processed, so a migration plan should not promise unchanged rankings or instant recovery.
Takeaway: Treat a migration as a controlled change with an inventory, ownership and checks. Preserve useful content and relevant routes rather than relying on a broad redirect to the homepage.
Example
A service business changes its CMS but wants to keep its existing page addresses. The team verifies those addresses and forms before cutover instead of inventing redirects for unchanged URLs. Where one outdated address genuinely changes, it receives a specific relevant mapping and a test of the destination.
What to check
Keep old-to-new mappings where needed and verify the final HTTP behavior, content, canonical and indexability of important pages. Update internal links to intended destinations. Separate unrelated redesign or content changes where feasible so failures are easier to diagnose.
For more detail, see Site moves with URL changes.