SEO Migration: The Complete Checklist to Move a Site Without Losing Traffic

An SEO migration is the riskiest project a marketing team runs on a website: years of accumulated rankings, backlinks and AI citations sit on URLs that are about to change. Google documents the process in its guide to site moves with URL changes. This article turns it into a practical checklist.

What counts as an SEO migration?

Any change that alters URLs, content or the signals search engines rely on. The most common types:

• Domain change: rebranding, moving from a country domain to a .com, merging two brands.
• Protocol change: HTTP to HTTPS, or a switch between www and non-www.
• Platform change: moving from WordPress to Shopify, from Webflow to a custom stack, or between any two CMS.
• URL structure change: new folders, removed dates, translated slugs, flattened categories.
• Redesign: new templates that change headings, content blocks, internal links or page speed.
• Site merge or split: consolidating several sites into one, or moving a section to a subdomain.
• International restructuring: moving languages from parameters to folders, or from subdomains to folders.

Why do sites lose traffic after a migration?

The causes are almost always the same, and all of them are avoidable:

1. Missing or wrong redirects: old URLs return 404, or everything redirects to the home page, which Google treats as a soft 404.
2. Redirect chains: A redirects to B which redirects to C, which slows crawling and dilutes signals.
3. Lost content: shorter pages, removed paragraphs, deleted FAQ blocks or category texts.
4. Changed titles and headings on pages that ranked well.
5. Broken internal links still pointing to old URLs.
6. A blocked site: a staging robots.txt or a noindex tag pushed to production.
7. Missing technical tags: canonicals pointing to the old domain, incomplete hreflang, sitemap listing old URLs.

Before the migration: the preparation checklist

1. Take a complete inventory of the current site

Crawl the whole site with a crawler such as Screaming Frog and export every URL with its status code, title, H1, canonical and word count. Add the URLs from your XML sitemaps, from Google Search Console (pages with impressions) and from your analytics tool (pages with sessions), plus the URLs that receive backlinks. This list is your reference: nothing on it should disappear by accident.

2. Record the baseline

Export positions, clicks and impressions per page from Search Console, organic sessions and conversions per landing page, and the number of indexed pages. Note which pages are cited by ChatGPT, Gemini or Perplexity for your key questions. Without a baseline, you cannot tell a normal fluctuation from a real loss.

3. Build the redirect map

Match every old URL to its closest new equivalent, one to one, in a spreadsheet. Use 301 (permanent) redirects. Redirect a deleted product to its category, not to the home page. Keep the same content on the target page whenever possible. Remove chains: each old URL must reach its final destination in a single hop. You can learn more about how a 301 redirect transfers signals.

4. Check the new site in staging

Protect the staging environment with a password rather than only a robots.txt rule. Compare titles, meta descriptions, H1, body content, structured data, canonical tags and hreflang between the old and the new version, page by page for your top pages. Test page speed on mobile.

During the launch: what to do on migration day

1. Remove the staging protection and any noindex tag, and check robots.txt.
2. Activate the redirects and test a sample of old URLs, including the top 100 pages by traffic, with a redirect checker.
3. Update internal links so that they point directly to the new URLs instead of relying on redirects.
4. Publish an XML sitemap with the new URLs and submit it in Search Console.
5. For a domain change, verify both domains in Search Console and use the Change of Address tool.
6. Keep the old domain and its redirects active: Google recommends keeping redirects for as long as possible, generally at least one year.

After the migration: monitoring for 3 months

Crawl the old URL list again and confirm that every URL returns a single 301 to a page that answers 200. In Search Console, watch the indexing report, crawl errors and the evolution of clicks per page. Compare with the baseline every week. A temporary dip in the first weeks is normal; Google indicates that a medium sized site can take a few weeks to be fully processed, and larger sites longer. A page that keeps losing traffic after a month needs a check: wrong redirect target, missing content, or changed title.

Also update every external profile you control (social networks, directories, Google Business Profile) with the new URLs, and ask the sites that link to you most to update their links.

How does a migration affect your visibility in AI answers?

ChatGPT, Gemini, Perplexity and Google AI Overviews cite URLs. When an old URL returns a 404, the citation leads nowhere and the AI eventually finds another source, often a competitor. Redirects protect those citations in the same way they protect rankings. After launch, check that your brand is still cited on your key questions and that the cited links resolve to the new pages. The free Sorank Chrome extension helps you check titles, tags and on-page issues of the new pages one by one.

SEO migration checklist at a glance

A successful SEO migration is mostly preparation: a complete URL inventory, a one to one redirect map and a measured baseline. Once the new site is stable, it is the right moment to grow again: Sorank automates SEO and GEO by publishing optimized articles on your new site and tracking your presence in the AI.