TL;DR: Any major change to a website’s platform, domain, URLs, or structure that affects how search engines rank it.
In a nutshell
Website migrations cover platform swaps, domain changes, HTTPS upgrades, URL restructures, and redesigns with new URLs. They’re high risk because poor execution can lose 40-60% of organic traffic. Example: forgetting to map 301 redirects when moving from Squarespace to WordPress can wipe years of accumulated ranking authority overnight.
Quick answer: A website migration is any major change that affects how your site is structured or served: changing platforms, moving domains, restructuring URLs, redesigning major sections. Migrations are where SEO traffic frequently goes wrong: a poorly executed migration can lose 50% of organic traffic for months. With proper planning and post-launch monitoring, migrations preserve rankings.
What Are Website Migrations?
A website migration is any significant change to a website’s structure, URL architecture, hosting, platform, or domain that can affect how search engines index and rank it.
Think of it like moving your entire business to a new building. If you don’t tell anyone the new address, your customers will keep turning up at the old place, or worse, stop coming altogether. A bad migration can cost you 40 to 60% of your organic traffic overnight.
Types of Website Migration
- Domain migration: Moving from one domain to another (e.g. rebranding)
- HTTP to HTTPS: Adding an SSL certificate across all URLs. See our HTTPS/SSL entry.
- Platform migration: Moving from one CMS to another (e.g. Squarespace to WordPress)
- URL restructure: Changing URL formats or folder structures
- Site redesign with URL changes: Combining a visual overhaul with structural changes
Why Migrations Are High Risk
Search engines need time to re-crawl and re-index changed URLs. Without proper 301 redirects, old URLs return 404 errors and you lose all the link equity built up over time. Watch out for redirect chains after migration, too. Google’s migration guidance is in the Google Search Central documentation.
How to Migrate Safely
- Pre-migration audit: Crawl the site and record every live URL
- Redirect mapping: Map every old URL to its new destination
- Redirect implementation: Set up 301 redirects before launch
- Post-migration monitoring: Track rankings, traffic, and coverage errors in Search Console
- Update Google: Submit a new XML sitemap and request indexing
For broader pre-launch best practice, the web.dev learning library covers performance and CWV checks worth running before going live.
BrisTechTonic Migration Support
Our website migration service covers the full process, pre-migration audit, redirect mapping, implementation support, and post-launch monitoring.
Frequently Asked Questions
What are the most common migration mistakes?
Five recur often. Forgetting 301 redirects from old URLs to new ones. Changing URL structure without redirect mapping. Losing meta titles and descriptions during the move. Breaking schema or canonical tags. Submitting an outdated sitemap to Search Console. Each can be prevented with a thorough pre-launch checklist.
How do I migrate a site without losing SEO?
Three phases. Pre-launch: map every URL change, document existing meta and schema, audit current rankings. Launch: implement 301 redirects, update sitemaps, verify HTTPS configuration. Post-launch: monitor Search Console daily for first 30 days, fix any redirect issues immediately, track ranking changes against baseline.
How long do migrations take to recover from?
When done well: rankings stabilise within 2-4 weeks. When done badly: 3-6 months for partial recovery, sometimes never fully back to pre-migration levels. The difference is whether 301 redirects and content preservation are handled properly.
Should I migrate during a peak period?
Avoid if possible. Migrating during peak traffic periods means any short-term ranking dip costs the most revenue. Migrate during quieter periods so you have buffer time to fix any issues before peak demand returns.
Take this further
Site migrations are make-or-break SEO events. We’ve guided dozens of clients through migrations with rankings preserved or improved.
Ready to apply this to your own site? Book a free discovery call, or explore our SEO strategy service.