Website Migration SEO Checklist: How to Move a Site Without Losing Traffic

Website migrations are where a lot of hard-won organic traffic disappears. A redesign, a move from WordPress to Shopify, a new domain or a switch to HTTPS can all look finished from the front end while quietly breaking hundreds of URLs, internal links and signals Google relied on. This checklist covers the steps I follow before, during and after a migration.

Types of website migration and their SEO risk

Migration type	Example	Typical risk
Protocol	HTTP to HTTPS	Low, if redirects are clean
Design only	New theme, same URLs and content	Low to medium
Platform (CMS) change	WordPress to Shopify	Medium to high, URLs usually change
URL structure change	New category paths or slugs	High
Domain change	Rebrand to a new domain	High
Site merger or split	Combining several sites into one	Very high

The more things change at once, the harder it is to diagnose problems afterward. If you can, avoid changing domain, platform, URLs and content all in the same launch.

Phase 1: Before the migration

1. Benchmark everything

• Export 12 to 16 months of Search Console performance data by page and by query.
• Export analytics landing page traffic and conversions.
• Record rankings for your priority queries.
• Save the current indexed page count from the Page indexing report.

A baseline SEO audit at this stage also catches existing problems, so you do not migrate them or mistake them for new ones later.

2. Build a complete URL inventory

Combine URLs from a full crawl, XML sitemaps, Search Console, analytics landing pages, and your backlink tool’s list of linked pages. Each source catches URLs the others miss, especially old pages that still earn links.

3. Create the redirect map

• Map every old URL to its most relevant new equivalent, one to one where possible.
• Use 301 (permanent) redirects.
• Avoid redirecting large numbers of pages to the homepage. Google tends to treat irrelevant redirects like soft 404s.
• Prioritize pages with traffic, conversions or backlinks; check them manually.
• Plan to update, not just redirect, internal links in content and navigation.

4. Preserve on-page SEO elements

For every important page, carry over the title tag, meta description, H1, main body content, image alt text, structured data and canonical tags. Content that is cut during a redesign is one of the most common causes of ranking losses after launch.

5. Plan international and special cases

If you run multiple language or country versions, every hreflang reference must be updated to the new URLs at the same time. A careful hreflang implementation avoids one market quietly vanishing after launch. Also plan for paginated series, faceted navigation rules, and PDFs or other files that have links.

Phase 2: Testing on staging

1. Block staging from indexing with password protection rather than relying on robots.txt alone.
2. Crawl the staging site and compare against the old crawl: page count, titles, H1s, word counts, canonicals and status codes.
3. Test the redirect map with a crawler in list mode. Every old URL should return a single 301 to a 200 page, with no chains.
4. Check rendering of key templates, especially if the new platform relies on JavaScript.
5. Verify structured data on product, article and local business templates.
6. Test Core Web Vitals on the new templates. A slower site can offset other gains.
7. Prepare robots.txt and XML sitemaps for the live environment.

Phase 3: Launch day

• Remove staging password protection and any noindex tags. This is the most frequently missed launch step.
• Deploy redirects and spot-check top pages immediately.
• Submit new XML sitemaps in Search Console. For a domain change, use the Change of Address tool and keep both properties verified.
• Check analytics tracking and conversion events on the new site.
• Crawl the live site to confirm status codes and canonicals.

Phase 4: After the migration

1. Monitor Search Console daily for the first two weeks, then weekly. Watch the Page indexing report for new 404s, redirect errors and spikes in excluded pages. If new URLs pile up as crawled but unindexed, start with our guide to diagnosing unindexed pages.
2. Compare traffic by page against your benchmark, not just sitewide totals.
3. Fix 404s that receive traffic or links by adding missing redirects.
4. Update external profiles and high-value backlinks to point directly to new URLs where possible.
5. Keep redirects in place for at least a year, and ideally permanently.

How much traffic loss is normal after a migration?

A short dip of a few weeks is common while Google recrawls and reprocesses the site, especially for domain changes. A well-executed migration should recover to the pre-launch baseline within roughly one to three months. Declines that deepen or persist beyond that usually point to missing redirects, lost content, broken internal links or rendering problems. Having technical SEO support on hand for the first month after launch is the cheapest insurance against that.

Frequently asked questions

Do 301 redirects pass all ranking signals?

Google has said that 301 and other server-side redirects do not lose PageRank. In practice, results depend on the new page being a genuine equivalent of the old one, with similar content and intent.

How long should I keep redirects after a migration?

At least one year, and permanently if possible. External links and bookmarks to old URLs can continue for many years.

Should I migrate and redesign at the same time?

Ideally not. Changing URLs, content and design in one launch makes it hard to identify what caused any drop. If you must combine them, keep content and URLs as stable as possible.

What is the most common SEO migration mistake?

Launching with noindex tags or robots.txt rules left over from staging, followed closely by incomplete redirect maps that skip older pages with backlinks.