The Migration That Lost 90% of Its Traffic

A site migration is the single highest-stakes moment in search. Done well, you carry years of accumulated ranking authority intact onto a faster, cleaner platform and often come out ahead. Done badly, you can erase a decade of equity in a matter of weeks, and the recovery is measured in quarters, not days. The difference is rarely the new design or the new domain itself. It is whether the technical signals that tell Google "this page is the same valuable page, just at a new address" survive the move. The case below shows exactly how that goes wrong, and what it takes to claw it back.

The situation

A multinational media company (a cryptocurrency news publisher) moved its Brazilian property from a country-code structure, xx.com.br, to a subdomain structure, br.xx.com, in January 2022. As documented by Search Engine Land, daily organic clicks for that property ran at roughly 15,000 to 25,000 in December 2021. A year later, in December 2022, the same property was generating just 2,000 to 4,000 daily clicks. That is a year-over-year collapse of about 90 percent, against an internal forecast that had projected the property climbing past two million clicks per month.

What went wrong

The redesign and replatform looked fine to a human visitor. To Google it was broken. The migration generated soft 404s at scale: pages that returned a "success" status to crawlers while serving little or no real content. The count started at 1,193 affected pages in Brazil and grew to more than 120,000 soft 404s across the company's thirteen domains. In Brazil alone, 513,369 pages sat in "crawled, currently not indexed" limbo. Redirects were not consolidating authority cleanly, so the old domain kept absorbing crawl budget instead of passing signals forward, and auto-generated thin pages (currency converters) burned through what crawl budget remained. For a news site, where indexing speed is everything, a 24-hour lag to index meant stories were stale before they could ever rank.

The result

Recovery did not begin until the technical root causes were addressed, starting late January 2023, roughly a year after the move. The team returned correct HTTP status codes for genuinely missing pages, noindexed or removed the auto-generated thin content, and reclaimed crawl budget through robots.txt rules and canonicalization. Within twelve weeks, soft 404s across all domains fell about 83 percent (from roughly 120,000 to under 20,000), and Brazil's "crawled, not indexed" backlog dropped about 57 percent (513,000 to 220,000). Traffic began returning across multiple properties. The lesson is blunt: the problem was invisible in a browser and only surfaced in crawl and index reports, and it cost a full year before anyone fixed it.

Why it matters for you

If you are weighing a domain move, replatform, or redesign, the takeaway is not "do not migrate." It is "the visible product is the easy part." Google's own official guidance for a site move with URL changes is specific and unglamorous: use server-side 301 or 308 permanent redirects, submit a Change of Address in Search Console, keep the redirects live for at least a year so ranking signals transfer, update and resubmit your sitemap, and actively monitor the Index Coverage report for crawl errors. Every failure in the case above maps to one of those steps being skipped or broken. The cheapest insurance is a pre-launch crawl that catches soft 404s, redirect chains, and orphaned pages before they reach production, plus daily index monitoring for the first several weeks after launch when problems are still reversible. A migration that ships clean preserves equity. A migration that ships broken can lose 90 percent of it and take a year to notice.

Sources: Case study and all figures from Search Engine Land, "How soft 404s and indexing issues caused a 90% traffic collapse." Migration best-practice steps from Google Search Central, "Site move with URL changes."