Website migration: complete guide

How to migrate your website without losing rankings, traffic or your sanity

10 min

A website migration is one of the highest-risk moments for a site’s SEO and organic traffic. Changing domains, CMS, URL structure or technology can cause traffic drops of 30–70% if not executed correctly. Many companies take months to recover their previous rankings.

However, a well-planned migration can not only preserve existing traffic but also improve performance, user experience and search visibility. The key lies in thorough preparation, a complete redirect plan, rigorous testing and intensive post-migration monitoring.

Types of website migration

Not all migrations are equal. The risk level and complexity vary enormously depending on what changes. Understanding the migration type is the first step to planning it correctly.

  • Domain change: same content, new domain. High risk: Google must transfer all authority
  • Protocol change: HTTP to HTTPS. Low risk if managed correctly with redirects
  • URL structure change: new paths for the same content. Medium-high risk: requires a complete redirect map
  • CMS or technology change: WordPress to Astro, Shopify to custom, etc. High risk: the entire stack changes
  • Redesign with content changes: new structure, rewritten or removed content. Very high risk: directly affects rankings
  • Site consolidation: merging multiple domains into one. High risk: requires redirect and content strategy

Pre-migration audit

Before migrating, you need a complete inventory of what you have. Without this snapshot of the current state, you won’t be able to measure the migration’s impact or detect errors after launch.

  • Full crawl of the current site: all URLs, status codes, metadata, internal links (Screaming Frog, Sitebulb)
  • Organic traffic by URL: identify the pages generating the most traffic to prioritise them in the migration
  • Backlinks: export the external link profile from Google Search Console, Ahrefs or Semrush
  • Current rankings: document your main keyword positions as a post-migration reference
  • Indexed content: compare pages in the sitemap with those Google has indexed (Search Console > Indexing)
  • Performance baseline: record Core Web Vitals, load times and key metrics for the current site

Redirect plan

The redirect map is the most critical element of any migration. Every URL on the old site that has traffic, backlinks or rankings must redirect with a 301 (permanent) to its equivalent on the new site. 302 (temporary) redirects do not transfer SEO authority.

Do not use catch-all redirects pointing everything to the homepage. Each old URL should redirect to the most relevant page on the new site. If a page is removed without an equivalent, redirect to the parent category or the most related page.

  • Map old URL → new URL for every page with traffic or backlinks
  • Use 301 (permanent) redirects, not 302 (temporary)
  • Avoid redirect chains: old URL → intermediate URL → final URL reduces authority transfer
  • Implement redirects at the server level (htaccess, nginx, Vercel config), not with JavaScript
  • Test each redirect before launch with tools like httpstatus.io or curl

SEO preservation

Beyond redirects, there are SEO elements that must be maintained or improved during the migration. Losing metadata, structured data or internal links can have as much impact as failing to redirect URLs.

  • Titles and meta descriptions: migrate optimised metadata or improve it — don’t lose it
  • Structured data (schema.org): ensure the new site maintains or extends the markup
  • Canonical tags: verify each page has a correct canonical pointing to the new URL
  • XML sitemap: generate a new sitemap with all new site URLs and submit it to Search Console
  • Robots.txt: ensure it doesn’t block important new pages by mistake
  • Internal links: update internal links to the new URL scheme — don’t rely solely on redirects

Pre-launch testing

Thorough testing before launch is what separates a successful migration from a disaster. Work in a staging environment that replicates the production setup and verify every critical aspect.

  • Redirect verification: test a significant sample (100% of pages with traffic at minimum)
  • New site crawl: compare with the previous crawl. Are URLs missing? Are there 404 errors?
  • Performance: compare Core Web Vitals of the new site with the old site baseline
  • Functionality: forms, internal search, cart, login, critical user flows
  • Responsive: verify on mobile, tablet and desktop across different browsers
  • Accessibility: basic audit with axe DevTools and keyboard navigation

Rollback plan

You should always have a plan B. If something goes wrong during migration, you need to be able to revert to the old site quickly without data loss.

Define clear criteria for triggering a rollback: traffic drop greater than X%, 500 errors on more than Y% of URLs, broken critical features. Don’t wait days to decide: the first hours are crucial.

  • Keep the old site operational and accessible for at least 2 weeks post-migration
  • Document the exact steps to revert: DNS, server configuration, database
  • Define who has authority to make the rollback decision and how it’s communicated
  • If using a different hosting provider, keep the old contract active as a backup

Post-migration monitoring

The first 4 weeks after migration require daily monitoring. Some issues only surface with real traffic and field data. A temporary 10–20% drop in organic traffic is normal while Google re-indexes, but larger drops require immediate investigation.

  • Google Search Console: monitor crawl errors, index coverage and organic performance daily
  • Analytics: compare traffic, conversions and engagement metrics with the previous period
  • Server logs: look for patterns of 404 errors, 500 errors or wasted crawl budget
  • Core Web Vitals: verify field metrics improve (or at least hold steady) against the baseline
  • Backlinks: check that major external links correctly point (or redirect) to the new URLs

Key Takeaways

  • Audit the current site thoroughly before migrating: URLs, traffic, backlinks, rankings
  • The 301 redirect map is the most critical element: every URL with value must redirect correctly
  • Preserve SEO metadata, structured data and internal links during the migration
  • Test exhaustively in staging before launch: redirects, performance, functionality
  • Have a clear rollback plan and monitor daily for the first 4 weeks

Planning a website migration?

We plan and execute the migration to preserve your SEO, minimise risk and use the change as an opportunity to improve.