Site Migration
In one line
Site migration is any change that touches the substance of a site — domain, platform, URL structure, redesign — and historically the project where SEO equity is most at risk.
Going deeper
Site migration covers everything from a domain change to a platform swap (WordPress to headless, say), a full URL restructure, or a complete redesign. So much shifts at once that 30 to 70 percent traffic drops, with multi-month recoveries, are not unusual.
Two things matter most in practice. The first is a complete 1-to-1 redirect map from old URLs to new. The second is pre-launch baselining — crawl, log, ranking and conversion data captured the same way before and after — so that any post-launch loss can actually be diagnosed instead of guessed at.
GEO adds one more wrinkle: LLMs tend to cite the URLs they were trained on, so a domain change leaves old citations in the wild for a while. Clean 301 mapping speeds up not just classic SEO recovery but the AI-citation update too.
Related terms
301 Redirect
A 301 redirect is the HTTP status code that says a URL has moved permanently — passing essentially all of the original page's link equity to the new URL.
SEO308 Redirect
A 308 redirect is the modern permanent redirect — same long-term meaning as 301, but it preserves the original request method instead of forcing GET.
SEORedirect Chain
A redirect chain is when a URL has to pass through two or more redirect hops before reaching its final destination — costing crawl budget, page speed and a slice of link equity along the way.
SEOSite Architecture
Site architecture is how you organise pages into categories and connect them via internal links — the structure that tells both search engines and AI what your site is really about.
SEOInternational SEO
International SEO is the discipline of running a site across multiple countries and languages — keeping hreflang, domain structure and localisation aligned so each market gets the right version.