Website migration is the process of moving your website from one location to another. This can mean: changing domains (example.com to newexample.com), switching servers, switching CMS (from WordPress to Webflow), or website relaunch with new architecture. A poorly executed migration can lead to massive SEO losses. A well-executed migration is nearly transparent.
What is website migration?
There are different types of migrations with varying complexity:
- Domain migration: newsite.de to newsite.com (greatest SEO risk)
- Protocol migration: http to https (low risk)
- Server migration: From one server to another (minimal risk if URL stays the same)
- CMS migration: From one platform to another (high risk, complicated)
- Structure migration: Website architecture reorganization (high risk)
- Mobile migration: Separate mobile website to responsive website (low to medium)
Each type of migration requires different strategies but all require planning, testing and monitoring.
Website Migration in SEO Context
Website migrations are critical for SEO because Google has bound your ranking power to your URL structure, links, and domain. If you do not migrate properly:
- Google might not find your new website
- Old rankings and backlinks might not "follow"
- You could lose 50-90% of traffic
- The rebuild process can take 6-12 months
A properly executed migration with 301 redirects and Google console signaling should have minimal traffic losses.
Website Migration Checklist
A safe migration follows this process:
| Phase | Task | Timing |
|---|---|---|
| Planning | Create catalog (all URLs), plan migration strategy | 4-6 weeks before |
| Planning | Work out redirect mapping (old to new) | 4-6 weeks before |
| Planning | Inform stakeholders, get approvals | 4-6 weeks before |
| Technical | Build new website, test (staging) | 2-4 weeks before |
| Technical | Create XML sitemaps, configure robots.txt | 1 week before |
| Technical | Implement 301 redirects | Migration day |
| Launch | Switch DNS, new website goes live | Migration day |
| Post-launch | Monitoring, error handling, 24h support | After launch |
| Follow-up | Monitor Google console, optimize redirects | Weeks 1-4 after launch |
| Follow-up | Resubmit search console, monitor 6-12 weeks | Ongoing |
301 Redirects - The Foundation
301 redirects are the most valuable tool in a migration. A 301 redirect tells Google: "This old URL no longer exists. Use this new URL instead" and transfers approximately 99% of ranking power to the new URL.
Good redirect structure:
- Old: /seo-tips.html -> New: /blog/seo-tips/
- Old: /products/crm -> New: /crm-software/
- Old: /contact -> New: /contact-us/
Bad redirects (to avoid):
- Old: /seo-tips -> New: / (to homepage) - tells Google that all old URLs are not relevant
- Old: /old-category -> New: /new-category (non-thematic mapping)
- Redirect chains (301 to 301 to 301) - inefficient, Google does not like it
A professional migration with 1:1 redirect mapping (old URL to new, thematically relevant) is safest.
Domain migration - Highest risk
A domain migration (old-domain.de to new-domain.com) is the riskiest migration type. Google must:
- Understand the new domain as the "successor" of the old domain
- Transfer all ranking power and links
- "Deindex" the old domain
Extra steps for domain migration:
- Use the "change of address" tool in Google search console
- Update backlinks if possible (contact partners, PR, etc.)
- Monitor 6-12 months. Rankings can rebuild slowly
- Keep old domain 12+ months with redirects
- Expect longer recovery time (vs. other migration types)
A domain migration can lead to 30-50% traffic loss even if everything is done right. Recovery takes 6-12 months.
Technical SEO in Migrations
Sitemaps:
- Create an XML sitemap with all new URLs
- Resubmit in Google search console
- Monitor coverage reports for errors
Robots.txt:
- Update robots.txt on old domain to prevent re-crawling
- New domain robots.txt should be crawlable
- If you duplicate content during migration, use canonical tags
- Canonical tag should point to new URL
HTTPS/SSL:
- Ensure new website has HTTPS (https:// not http://)
- Valid SSL certificate
Content migration best practices
1. Never delete content without a redirect: If you delete pages, create 301 redirects to the new page or to the homepage. Do not just delete and get 404s.
2. Keep URL structure consistent where possible: If old URLs work, keep them. Only change if necessary for improvement.
3. Update metadata: Title tags, meta descriptions should be optimized while you are touching the content anyway.
4. Update internal links: Links from old to new structure should point directly to new URLs, not through redirects.
Monitoring and recovery after migration
First 48 hours (critical):
- Perform comprehensive testing to ensure pages load
- Ensure 301 redirects work
- Monitor error logs for issues
- Test on different devices and browsers
Week 1-2 (monitoring):
- Check Google search console daily
- Watch for crawl errors, indexing issues
- Monitor traffic movements
- Collect user feedback for broken functionality
Month 1-6 (recovery):
- Ongoing search console monitoring
- Watch rankings. Normal fluctuation is OK
- Optimize redirect performance if errors discovered
- Build backlinks for new domain if domain migration
Common migration mistakes
1. Change too many URLs at once: If you drastically change structure, Google can get overwhelmed. Small, manageable changes are better.
2. Delete old website immediately: Keep old website 6-12 months minimum. Some old links will still be out there.
3. Do not signal in Google console: Use the change of address tool for domain migrations. Very important.
4. Redirect to homepage instead of thematic new URL: Google interprets this as "this content no longer exists", not as "URL moved".
5. Be too hasty: Migrations need time and planning. Hasty migrations cause problems.
Website migrations are technically complex but doable if you plan carefully, test and monitor. A well-executed migration should have minimal SEO impact.