Website Migration SEO: How to Move Sites Without Losing Rankings

Website migrations are among the highest-risk SEO activities a business can undertake. Done well, they're transparent from a rankings perspective. Done poorly, they cause traffic losses that can take months or years to recover — and some sites never fully recover at all.

This guide covers the SEO requirements for site migrations: what to do before, during, and after the move to protect organic visibility.

What Counts as a Site Migration for SEO Purposes

A site migration is any change that significantly alters how your site is crawled and indexed. This includes: domain changes (moving from one URL to another), protocol changes (HTTP to HTTPS), CMS migrations (moving from one platform to another), URL structure changes (changing the path format of your pages), and site redesigns that significantly alter content or internal linking structure.

Pre-Migration: The Non-Negotiable Preparation Steps

Crawl and Benchmark Your Current Site

Before any migration begins, document the current state of the site completely: crawl every URL and record status codes, title tags, meta descriptions, H1 tags, word count, and canonical tags. Export all organic traffic data from Google Search Console and Google Analytics — ideally at the URL level. Record your current ranking positions for priority keywords. This baseline is essential for measuring the impact of the migration post-launch and identifying what has gone wrong if rankings drop.

Create a Complete Redirect Map

Every URL that exists on the current site that will change in the migration needs a 301 redirect to its new location. This is non-negotiable. Missing redirects lose the accumulated link equity, traffic, and ranking signals for those pages — they effectively become new pages with no history. The redirect map should be built before migration and tested exhaustively before launch.

Verify the New Site Before Launch

The new site should be audited in a staging environment before it goes live. Check that all pages are crawlable and indexable, that redirects work correctly, that canonical tags are properly configured, that internal links point to new URLs rather than relying on redirects, and that Core Web Vitals performance is at least equal to the existing site.

During Migration: Launch Day Protocol

Launch the migration in a single go rather than in phases where possible — partial migrations create complex redirect chains and confusing signals for Google. Immediately after launch: verify that the redirect map is live and working, submit an updated sitemap to Google Search Console, check that robots.txt is not blocking crawling of the new site, and monitor server logs for crawl errors.

Post-Migration: Monitoring and Recovery

The First 72 Hours

Monitor Google Search Console for crawl errors, coverage issues, and any manual action notifications. Check that your key pages are being indexed in their new locations. Monitor your analytics for traffic patterns — some temporary fluctuation is normal, but significant drops in the first 48 hours usually indicate a technical problem that needs immediate diagnosis.

Weeks Two Through Eight

Rankings often fluctuate for four to eight weeks following a migration as Google processes the new site structure and recalibrates its understanding of the content. Monitor rankings weekly for priority keywords, track index coverage, and verify that link equity is flowing correctly through redirects to new URLs.

Common Post-Migration Problems and Fixes

The most common post-migration issues are: missing or broken redirects (audit redirect coverage against the original URL list), new URLs returning errors (check for CMS configuration issues), duplicate content on old and new URLs simultaneously (check robots.txt and noindex settings on old site), and internal links still pointing to old URLs (update internal links to point directly to new URLs, not through redirects).