How to Migrate From "One Site Per Book" to a Hub Without Losing Rankings
Short answer: never delete the old site outright. Migrate content into subfolders or subdomains of the new hub, set up 301 redirects from every old URL to its new equivalent, and keep both live until you confirm in Google Search Console that traffic has transferred.
Why migrating poorly can cost you your rankings
When you change domains or structure without redirects, Google treats every new URL as if it never existed — losing overnight all the history and trust the previous site had built up.
The steps, in order
Before moving anything: export the full list of the old site's URLs from Google Search Console.
Prepare the hub's hosting: if you're consolidating several sites into one hosting account, confirm the plan supports the combined traffic and allows creating the needed subfolders or subdomains — Affiliate link: I may earn a commission if you purchase through this link.Hostinger has plans that scale well for this.
Set up 301 redirects from every old URL to its exact new location, not just to the hub's homepage.
Update the sitemap and resubmit it in Search Console.
Monitor for 4-6 weeks the impressions and clicks of migrated pages before shutting down the old hosting.
A 301 redirect tells Google the content moved permanently, transferring most (though not 100%) of the authority the original URL had accumulated.
Official Google Search Central documentation on redirects, 2026