You redesign the site, move it to Shopify or WordPress, change the domain… and three weeks later your organic traffic has collapsed. It's not bad luck and it's not a Google penalty: it's a poorly planned website migration. The redesign itself doesn't cost you rankings; what costs you rankings is changing everything without a plan so Google keeps understanding your site.

The good news is that a migration can be done without losing almost anything. The bad news is that it's dead easy to break invisible things —redirects, titles, internal links— that don't show on the new site but absolutely show in your numbers. This guide is written for the business owner: what's at stake, what to demand from whoever builds the new site, and how to make sure you don't lose the traffic you already paid for in time and effort.

What a migration is (and why a redesign is one too)

To Google, a website migration is any significant change to your site: the domain, the page addresses (URLs), the hosting, the platform or the design. You don't need to move to a new domain to be migrating.

This surprises a lot of people: a redesign is also a migration. If you rebuild the site and the URLs, the menu structure, the titles or the way pages link to each other change along the way, you're moving the very pieces Google used to build your rankings. The same happens when you switch platforms —from a custom build to WordPress, from WordPress to Shopify— or when you finally move from http to https.

A simple way to size up the risk:

  • Domain change (e.g. yourcompany.co → yourcompany.com): high risk, you have to tell Google.
  • Platform or CMS change (WordPress, Shopify, custom build): medium-high risk, the technical details change even if the URLs stay the same.
  • Redesign with URL or structure changes: high risk, this is where most traffic is lost.
  • Redesign that keeps the same URLs: lower risk, but you still have to check titles, content and speed.

Why you lose traffic when you redesign

Think of it this way: Google keeps a list of your pages, with their exact address, and has given them a position in the results over months or years. When you redesign, that address can change, the page can end up different, or it can disappear entirely. If you don't leave Google a clear path from the old address to the new one, what it built evaporates.

Post-migration drops almost always come from the same short list of causes, and none of them is a mystery:

  • Missing redirects. The old URL no longer exists and points to no new page. User and Google see a 404 error.
  • A leftover block from the staging site. While the new site is being built it's usually blocked so Google can't see it. If that block isn't removed at launch, Google can't get in.
  • A forgotten noindex tag, which explicitly tells Google "don't show this page".
  • Changed content or internal links. Text got "cleaned up", sections were removed, or the menu and the links between pages ended up different.
  • Content that doesn't load. On heavily JavaScript-based sites, Google sometimes doesn't see the text because it isn't loaded when it reads the page.

All of this is avoidable. Not with luck —with a plan and a review before you hit the button.

The 5 things you can't break

If your new site keeps these five things in order, 90% of the risk disappears.

1. The addresses and their redirects. Every old URL that had traffic or links must lead, via a 301 (permanent) redirect, to its equivalent on the new site. There's a myth worth burying here: 301 redirects don't cost you authority. Google says it literally in its official documentation: permanent redirects don't cause a loss of PageRank. The problem is never the redirect —it's the redirect that's missing.

2. Titles and content. The titles and descriptions of your ranking pages are part of why they rank. A new platform often generates them automatically and overwrites the ones you had. Same with text: if the new version of a page has half the content, it also has half the reasons to rank.

3. Internal linking. The links between your own pages —menu, breadcrumbs, related posts, footer— tell Google what matters on your site. A redesign that changes the navigation changes that map.

4. Canonicals and hreflang. These are technical tags that tell Google which is the "official" version of a page and, if you have versions in several languages, which one belongs to each. Get them wrong and Google may index the wrong page or mix up languages.

5. Speed. A new site that's heavier or slower can lose rankings even when everything else is perfect. Speed is part of the experience Google measures.

The website migration checklist that keeps your SEO

A migration plays out in three moments. Here's what has to happen in each —and what you, as the owner, can ask to be shown.

Before launch

  • A snapshot of the current state. An inventory of the URLs that have traffic and rankings today. Without this snapshot, there's nothing to compare against later if something drops.
  • An old → new URL map. A table where every important page today is assigned its page on the new site. It's the single most important document of the whole migration.
  • A rollback plan. If something goes wrong on switch day, there has to be a way back to the previous state.
  • A staging review. Before it goes public, check that titles, content, links and technical tags are correct.

During the switch

  • Turn on all 301 redirects from old to new.
  • Remove any block or noindex the staging site had.
  • Submit the new sitemap (the page map) to Google Search Console and, if you're changing domains, use the Change of Address tool in Search Console.
  • If you're changing domains, temporarily lower the DNS "time to live" a few hours ahead, so the change propagates fast.

After

  • A quick live test of the most important pages: that they open, redirect correctly, and that analytics and forms work.
  • Monitoring for 30 days: 404 errors, indexing, and traffic and rankings against the baseline snapshot.
  • Keep a sitemap with the old URLs for a short while, so Google finishes understanding the change.

One last principle that comes straight from Google and costs money to ignore: change one thing at a time. If you're going to move the domain, switch platforms and redesign, don't do it all on the same day. Google recommends this explicitly, because if something breaks with three changes at once, you won't know which one did it.

How we do it

In the migrations we run we work by one rule: no open task can be left pending at the moment of the switch. The deliverable isn't a thirty-tab document nobody reads; it's two simple sheets —one with the task checklist and its status, the other with the important URLs and every SEO parameter checked one by one.

To decide which URLs are "important" we don't guess: we use Search Console and keep the pages that hold 80% of the clicks, plus the key business pages. Those are the ones that have to survive no matter what. Then we map each one against its equivalent on the new site, verify that every old address resolves correctly (directly or via a redirect, with no chains or loops), and only when everything is green do we give the go-ahead to migrate.

The practical takeaway: most of a migration's risk isn't in the technology, it's in what nobody checked. An orderly process turns the most dangerous moment in SEO into a change with no surprises.

How long recovery takes

Let's be honest about the expectation: even doing everything right, it's normal to see ranking fluctuation in the weeks after. Google has to re-crawl and reindex your site, and that takes time. Its documentation talks about "a few weeks or more" for medium-sized sites, and longer for large ones.

That's not a drop: it's the period in which Google processes the change. The difference between a well-done migration and a botched one isn't that one has flux and the other doesn't —both do. The difference is that in the well-done one traffic returns to its level (or better), and in the botched one it stays down because signals were lost that don't come back on their own.

That's why monitoring the first 30 days isn't optional: it's when you catch a missing redirect or a page that fell out of the index, while it's still easy to fix.

Frequently asked questions

Can a redesign make me lose rankings on Google?

Yes, if redirects aren't planned and SEO parameters (titles, content, linking, technical tags) aren't controlled. The redesign itself isn't penalized; what hurts is redesigning without a plan and breaking the signals Google used to rank you.

Do 301 redirects lose authority?

No. Google confirms in its official documentation that permanent (301) redirects don't cause a loss of PageRank. The old page's authority passes to the new one. The problem is the missing redirect, not the one that's done right.

How long does Google take to recover my rankings after a migration?

On medium-sized sites, several weeks of fluctuation until Google reindexes everything; on large sites, longer. It depends on the size of the site and the speed of the server. Submitting the new sitemap speeds up the process.

Can I change domain, platform and design at the same time?

Not a good idea. Google recommends changing one thing at a time so you can isolate any problem. If you do it all at once and traffic drops, you won't know what caused it.

What's the first thing I should ask for before launching the new site?

Two things: the old → new URL map with its 301 redirects, and a snapshot of the current state (which pages have traffic and rankings today). With those you already have what you need to make sure nothing is lost.