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Technical SEO

How to redesign or migrate a website without losing rankings

15 June 2026 · 8 min read · Coselli, Bournemouth

Redesigns are the most common cause of catastrophic traffic loss in small business SEO. The plan that prevents it is not complicated — it is just rarely followed.

A redesign changes URLs, templates, content and sometimes the domain all at once. Any of those alone is manageable; all four unmanaged is how sites lose 60% of their organic traffic overnight. Here is the sequence that prevents it.

Before you build: benchmark

  1. 01Crawl the entire existing site and export every URL.
  2. 02Export twelve months of Search Console data — queries, pages, clicks, impressions.
  3. 03Export analytics landing page performance and conversion data.
  4. 04List your top 50 pages by traffic and by revenue. These are non-negotiable survivors.
  5. 05Record current rankings for your key terms so you can measure the change.

During the build: map and preserve

  • Keep URLs identical wherever you possibly can. The best migration changes no URLs at all.
  • Where URLs must change, build a one-to-one redirect map. Old URL, new URL, no chains, no bulk redirects to the homepage.
  • Carry over the content that earns the rankings. A prettier page with a third of the copy usually ranks worse.
  • Preserve titles, meta descriptions, headings and structured data unless you are deliberately improving them.
  • Block the staging environment with authentication, not just robots.txt.

Pre-launch checklist

  1. 01Remove any noindex left over from staging — check the rendered HTML of every template.
  2. 02Verify robots.txt allows the site.
  3. 03Test every redirect from the map, including https and www variants.
  4. 04Confirm canonicals self-reference on the new URLs.
  5. 05Regenerate the XML sitemap with only new, live, canonical URLs.
  6. 06Check analytics and conversion tracking fire on the new templates.
  7. 07Run Core Web Vitals on the main templates.

Launch day

  • Deploy at a low-traffic window.
  • Immediately crawl the live site looking for 404s, redirect chains and missing metadata.
  • Submit the new sitemap in Search Console; if the domain changed, use the Change of Address tool.
  • Watch server logs for crawler errors for the first 48 hours.

The first ninety days

Expect some fluctuation for two to four weeks; that is normal as Google reprocesses the site. What is not normal is a sustained decline. Check the Page Indexing report weekly, compare query-level performance against your benchmark, and fix the specific pages that dropped rather than panicking site-wide.

Keep the old crawl export and redirect map for a year. Almost every post-migration mystery is solved by a URL nobody remembered.

Frequently asked

How long does it take to recover after a migration?
A well-executed migration usually stabilises within two to four weeks. If traffic is still materially down after eight weeks, something structural is wrong — usually redirects or missing content.
Can I change my domain name safely?
Yes, with a full one-to-one redirect map, the Change of Address tool in Search Console, and updates to every external listing and citation pointing at the old domain.

Keep reading

Technical SEO

Technical SEO foundations every website needs

Content and links cannot rescue a site search engines cannot crawl, render or trust. The technical baseline, explained without jargon.

Performance

Core Web Vitals and site speed: what to fix first

Three metrics, a handful of fixes, and a measurable jump in conversions. What Core Web Vitals actually measure and how to improve them without a rebuild.

Content

The on-page SEO checklist for every page you publish

A short, repeatable checklist that catches the on-page mistakes costing most sites their easiest rankings.

Let’s build the site this advice is written for.

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