The strategy that prevents loss after a CMS migration is a complete one-to-one map with direct server-side permanent redirects. A CMS migration moves content from one publishing system to another, often changing URLs, slugs, or site structure. Google Search Central states in its site-move guide with URL changes that each old URL needs its closest-topic new counterpart. That match preserves relevance and passes ranking signals to the right destination.
Official resources:
- Follow Google's site-move checklist for URL changes — Map every old URL one-to-one, use single-hop permanent redirects, and monitor traffic and indexing after migration.
- Use permanent server-side redirects for moved pages — Verify when to use 301 or 308 so Google transfers canonical status to the new URL instead of keeping the old one.
Table of Contents
- Inventory and match every important URL
- Why permanent redirects matter?
- Keep each redirect direct and durable
- Update links, sitemaps, and Search Console
Inventory and match every important URL
Start before launch with a full list of crawlable, indexed, traffic-driving, and linked URLs. Pull data from crawls, analytics, Search Console, backlink reports, and the old sitemap. Missing pages become 404s and lost visits.
Map each old address to the closest-topic new address, not to the homepage. A blog post goes to its new post URL. A product page goes to its new product URL. A category goes to its new category.
- Keep the old URL, new URL, status code, and content match in one sheet.
- Flag deleted items for a relevant parent or section, not the homepage.
- Review redirects for thin, duplicate, or merged pages individually.
Why permanent redirects matter?
Use HTTP 301 or 308 for permanent CMS URL changes. Google Search Central explains in its redirects guide that permanent redirects signal the target should become the canonical URL in results. That canonical transfer is the core protection for visibility.
Do not use temporary 302 or 307 redirects for permanent moves. Google keeps showing the old source URL instead of transferring canonical status. The result is split signals, slower reindexing, and weaker performance for the new pages.
Keep each redirect direct and durable
Point each old URL straight to its final destination in one hop. Avoid chains where A points to B, then B points to C. Avoid loops where URLs point back to each other.
Extra hops add latency and create crawl failure points. Crawlers may abandon the path before reaching indexable content. Test the live map with a crawler and fix chains, loops, and 404s before announcing the move. Keep redirects live as long as possible, generally at least one year, so old URLs can be recrawled and signals transferred.
Update links, sitemaps, and Search Console
Stop depending on redirects for normal navigation after launch. Update internal links, canonical tags, navigation, feeds, and XML sitemaps to reference the new final URLs directly. Submit the new sitemap in Search Console and watch coverage for old URLs, new URLs, and 404s.
For a domain or subdomain change only, verify both properties and submit a Change of Address after 301s are live. Google Search Console Help notes in its Change of Address instructions that the tool does not create redirects and does not cover path-only or HTTP-to-HTTPS moves. Even with perfect redirects, expect ranking fluctuation for weeks or longer while pages are recrawled, so retain the old domain and monitor traffic and indexing.
