Website migrations are high-stakes SEO events. A poorly executed migration can wipe out years of organic search visibility in days. We have seen businesses lose 40-60% of their organic traffic because redirects were missed, canonical tags were misconfigured, or internal linking structures were broken during the transition. This guide covers the systematic approach we use to protect rankings through every migration.
Pre-Migration: The Audit Phase
Before touching code or design, establish a comprehensive baseline:
- Crawl the existing site: Use Screaming Frog or Sitebulb to crawl every URL. Document the full URL structure, page titles, meta descriptions, canonical tags, and internal links.
- Identify high-value pages: Export your top-performing pages from Google Search Console and Analytics. These are the pages where a redirect failure would cause the most damage.
- Record current rankings: Track keyword positions for your most important terms. This gives you a clear before-and-after comparison.
- Map backlinks: Use Ahrefs or Moz to identify all external links pointing to your site. Every URL with backlinks must redirect correctly — backlink equity does not transfer without proper 301 redirects.
The Redirect Map
The redirect map is the most critical deliverable in any migration. It is a spreadsheet mapping every old URL to its corresponding new URL. Every single page, image, PDF, and resource that exists on the current site needs a destination. There are no shortcuts here — automated tools can help generate the initial mapping, but human review is essential to ensure logical content matching.
Use 301 (permanent) redirects, not 302 (temporary). Avoid redirect chains — old URL should point directly to the final new URL, not through intermediate redirects. Test every redirect before launch using tools like httpstatus.io or a custom script that crawls your redirect map and verifies each response.
Technical SEO Preservation
Beyond redirects, verify that the new site maintains critical SEO elements. Page titles and meta descriptions should carry over (improved where possible). Heading structure should remain logical with single H1 tags per page. Structured data (schema markup) should be reimplemented on the new platform. XML sitemaps should reflect the new URL structure and be submitted to Google Search Console immediately after launch.
Internal linking is often overlooked during migrations. If the old site had carefully constructed internal links that passed authority between related pages, the new site must replicate or improve on that structure. Do not rely on redirects for internal links — update all internal links to point to new URLs directly.
Post-Migration Monitoring
Monitor aggressively for the first 30 days. Check Google Search Console daily for crawl errors, coverage issues, and indexing problems. Watch for 404 spikes in your server logs. Compare organic traffic week-over-week against pre-migration baselines. Some temporary ranking fluctuation is normal — Google needs time to process URL changes — but sustained drops indicate redirect failures or technical issues that need immediate attention.
At Born Digital, website migration SEO is built into every redesign and replatforming project. We have handled migrations from WordPress to Astro, Magento to Shopify, and legacy platforms to custom builds — preserving and often improving organic visibility through methodical planning and execution. The technical work is straightforward; the discipline to do it completely is what separates successful migrations from disasters.