A safe migration comes down to four habits: inventory every URL before you start, build and test on a staging copy, map each old address to a new one with server-side redirects, and monitor closely after switching DNS. Moving platforms is mostly a data and routing exercise. The design may not change at all, yet the plumbing underneath does.
This guide focuses on the mechanics of a platform move. If the visual design and content are also changing, read how to plan a website redesign without losing SEO value alongside it.
Phase 1: Inventory and decisions
- List every URL. Google’s site move guidance suggests building the list from your sitemaps, top-traffic pages, server logs and the CMS, and including images, CSS and JavaScript. Export from more than one source because each misses something.
- Record what each page does. Traffic, backlinks, forms, tracking tags, structured content and embedded media.
- Decide the fate of each URL: keep, change, merge or retire. Not every page deserves a new home.
- Freeze the content for a short window before launch so the inventory does not drift.
- Choose the new platform on its merits. Astro vs WordPress compares two common options.
Phase 2: Build and test on staging
- Rebuild or import content, and transfer images and downloads such as PDFs.
- Keep staging out of search results with access protection rather than relying only on a noindex tag, and remove any noindex rules that were used during development before launch. Google specifically advises checking that the new site’s robots.txt blocks only what you intend.
- Add self-referencing canonical tags, update hreflang if you use it, and change internal links to the new URLs.
- Test forms, tracking, email delivery, search, and the 404 page.
- Confirm the server can cope with heavier crawling after the move.
- Compare speed with the old site. See Core Web Vitals for business.
Phase 3: The redirect map
Map each old URL to its closest new equivalent in a spreadsheet, then implement it at the server.
| Situation | Action |
|---|---|
| URL moves to a new address | Permanent server-side redirect (301 or 308) to the mapped page |
| Several old pages merge into one | Redirect them all to the merged page |
| Page is retired with no equivalent | Return 404 or 410 |
| Old URL has no related page | Do not send it to the home page |
Google’s guidance prefers server-side redirects, with client-side methods as a last resort, notes permanent redirects do not lose PageRank, and says to avoid chains: redirect straight to the final destination, keep chains to about 3 hops if unavoidable and never more than 5. It warns that sending many unrelated old URLs to the new home page can look like a soft 404. Its redirects documentation explains permanent versus temporary types.
Phase 4: DNS cut-over
- Lower the DNS time to live value a day or two ahead so changes propagate quickly (a general DNS practice, check your provider’s documentation).
- Verify the new site in Search Console, including every variant such as www and non-www and HTTP and HTTPS.
- Launch at a quiet time, with someone on call.
- Submit the new sitemap and keep the old one until the new one is indexed.
- Only use Search Console’s Change of Address tool for a domain or subdomain change, not for path changes or an HTTP to HTTPS move.
Phase 5: After launch
- Crawl the old URL list and confirm every redirect resolves in one hop.
- Watch the Search Console sitemap, indexing and queries reports, plus server logs and analytics. Google notes rankings may fluctuate, with medium sites taking a few weeks to settle.
- Keep redirects for at least a year, and longer where practical. Update internal links and key external links so people do not rely on them.
- Check forms and tracking daily for the first week. The redesign guide above has a launch-week checklist that overlaps with this list.
Limitations
A checklist cannot guarantee unchanged rankings. Platforms handle URL patterns, trailing slashes, and rendering differently, so test each pattern on staging. A migration is also a good moment to find out how much of the old site is worth keeping.
Where Radiance Impact fits
Radiance Impact’s Technology division builds business websites and redesigns. If you are weighing a platform move, see /technology or contact us.
Sources
- Site moves with URL changes, Google Search Central
- Redirects and Google Search, Google Search Central
