Domain migration (site move / change of address)

The technical-SEO operation of moving a site to a new domain while preserving its accumulated ranking and indexing. The pivotal mechanism is Google’s Change of Address tool in Search Console, which tells Google to transfer signals from the old domain to the new one alongside server-side 301 redirects.

The all-variants rule

Google’s guidance tightened in June 2026 (google-domain-migration-requirements): a migration now requires a separate Change of Address for every verified variant of the old domain — each subdomain, plus www and non-www — even variants that aren’t actively used. The reasoning is that internal and external linking patterns can make Google crawl variants the owner forgot about, so any unmigrated permutation becomes a leak that drags on the move’s ranking outcome. The practical cost is more Search-Console verification and bookkeeping up front, in exchange for a cleaner signal transfer.

The first-party procedure

Google’s own site-move doc (google-site-move-doc) spells out the mechanics:

• Permanent server-side redirects. Use 301/308; Google states “301 and other permanent redirects don’t cause a loss in PageRank.” Keep redirect chains short — “ideally no more than 3 and fewer than 5” hops.
• Keep redirects ~1 year. “Keep the redirects for as long as possible, generally at least 1 year” — the window Google needs to recrawl and “transfer all signals to the new URLs,” including reassigning inbound links from other sites.
• HTTP→HTTPS is exempt from the Change of Address tool entirely.
• Timeline. A small-to-medium site “can take a few weeks for most pages to move, and larger sites take longer.” Google advises changing one thing at a time and moving all URLs together rather than in sections. So the move is not instantaneous — there’s a measurable transition window during which signals are mid-transfer.

Where it sits

Domain migration is a traditional technical-SEO concern (operational rigor, redirects, index health), distinct from the AI-era visibility threads — but it shares the spoke’s recurring lesson that the authoritative procedure is first-party (GSC + Google docs), not third-party tooling. A failed migration surfaces as indexation loss across variants.

Related

google-site-move-doc · google-domain-migration-requirements · google-search-console · search-indexation · hyphenated-domains-seo · search-marketing