How to migrate a website without losing SEO

Website migrations are where most businesses accidentally destroy their SEO. They change URLs without setting up redirects, delete pages that drive traffic, or launch a new site without telling Google—and their rankings drop overnight.

A safe migration isn't complicated, but it requires a plan. This guide walks you through exactly what to do before, during, and after launch to protect your traffic.

What is a website migration?

A migration is any major change to your site that affects URLs, structure, or platform. Common examples:

Rebuilding your site on a new platform (WordPress to Webflow, old custom site to Next.js, etc.)
Changing your domain (oldcompany.com to newcompany.com)
Moving from HTTP to HTTPS
Redesigning and changing your URL structure
Merging two websites into one

If you're just updating copy or design without changing URLs, that's not a migration—you're safe.

If you're changing URLs, platforms, or domains, you need a migration plan.

Before launch: What to do first

Don't touch your live site yet. Do this prep work first:

1. Export your current URLs

You need a complete list of every page on your current site so you can map old URLs to new URLs.

How to get it:

Use your sitemap: Most sites have a sitemap at yoursite.com/sitemap.xml. Copy all the URLs from there.
Use a crawler: Tools like Screaming Frog (free for up to 500 URLs) will crawl your site and give you a complete list of URLs.
Check Google Search Console: Go to Coverage or Pages and see which URLs Google has indexed.

Put this list in a spreadsheet with two columns: Old URL and New URL.

2. Identify your top-performing pages

Not all pages are equal. Some drive 80% of your traffic. You need to know which ones.

Use Google Analytics (GA4):

Go to Reports → Engagement → Pages and screens
Look at the last 6–12 months of data
Export your top 20–50 pages by traffic

Use Google Search Console:

Go to Performance → Pages
Export the pages with the most clicks and impressions

These are your money pages. Losing rankings on these hurts. Protect them.

3. Map old URLs to new URLs

For every old URL, write down the new URL it should redirect to.

Rules for mapping:

If the page is staying and just changing URLs, map old → new.
If the page is being deleted but you have a similar replacement page, map old → replacement.
If the page is being deleted and there's no replacement, map old → most relevant category or homepage (as a last resort).

Example mapping:

Old: /services/hvac → New: /services/hvac-repair
Old: /blog/post-123 → New: /resources/post-123
Old: /old-page-nobody-visits → New: /services (or homepage if truly irrelevant)

This mapping becomes your redirect file.

4. Check content parity

Content parity means the new page has the same (or better) content as the old page.

If your old AC Repair page had 1500 words, photos, FAQs, and testimonials—and your new page has 200 words—Google sees that as a downgrade. Rankings will drop.

Go through your top-performing pages and make sure the new versions are comprehensive and complete.

5. Set up 301 redirects

A 301 redirect tells Google: 'This page moved permanently. Send users and rankings to the new URL.'

How to set them up depends on your platform:

WordPress: Use a plugin like Redirection or Yoast SEO Premium.
Webflow: Use the built-in 301 redirect tool in your site settings.
Custom site (Next.js, etc.): Set up redirects in your server config or next.config.js.
Server-level (Apache/Nginx): Edit your .htaccess or nginx.conf file.

Test your redirects before launch using a staging site or redirect checker tool. Make sure old URLs redirect to the correct new URLs—not 404s, not homepage, the specific correct page.

Launch day: What to do

You've done your prep. Now it's time to launch.

1. Launch the new site with redirects live

Make sure your 301 redirects are active the moment the new site goes live. Don't launch first and add redirects later—even a few hours of 404s can hurt rankings.

2. Submit your new sitemap in Google Search Console

Your sitemap is a file (usually at yoursite.com/sitemap.xml) that lists all your pages.

After launch:

Go to Google Search Console
Go to Sitemaps
Remove the old sitemap (if you're on a new platform and the URL changed)
Submit your new sitemap

This tells Google to crawl your new URLs faster.

3. Check your robots.txt file

Make sure your robots.txt file (yoursite.com/robots.txt) isn't accidentally blocking Google from crawling your site.

Common mistake: Developers block crawlers on staging sites, then forget to unblock them on launch.

After launch: What to monitor

Your job isn't done. You need to watch for problems and fix them fast.

1. Check Google Search Console for errors

Go to Search Console → Pages (or Coverage on older accounts).

Look for:

404 errors: Pages that used to exist but now return 'not found.' Fix these with redirects.
Redirect chains: Old URL → temporary URL → final URL. Clean these up so old URLs redirect directly to final URLs.
Soft 404s: Pages that look like errors to Google but return 200 status codes. Usually caused by thin content or broken templates.

Fix errors immediately. Every 404 is a page that used to rank and now doesn't.

2. Monitor rankings and traffic

Check Google Analytics and Search Console weekly for the first month after launch.

Watch for:

Traffic drops on specific pages (might mean a redirect is broken or content parity is off)
Overall traffic drops (might mean a technical issue like robots.txt blocking crawlers)
Ranking drops for specific keywords (check if the target page changed URLs and the redirect is set up correctly)

Small fluctuations are normal. Big drops (30%+ traffic loss) mean something is broken—investigate immediately.

3. Update internal links

Your redirects will handle external links and old bookmarks. But your internal links (links between pages on your own site) should point directly to new URLs—not rely on redirects.

Why? Because redirect chains slow down your site and dilute link equity.

Do a find-and-replace across your site to update internal links to the new URLs.

4. Update external links (if possible)

If you have links from important external sites (partners, directories, press mentions), reach out and ask them to update the URL to your new one.

This isn't always possible, but for high-value links, it's worth asking.

Common migration mistakes (and how to avoid them)

Launching without redirects: Results in massive 404 errors and traffic loss. Always set up redirects before launch.
Redirecting everything to the homepage: Lazy redirects (sending every old URL to your homepage) hurt rankings. Map old pages to the most relevant new page.
Deleting high-traffic pages without replacements: If a page drives traffic, don't delete it without a good replacement. If you must delete it, redirect to the closest relevant page.
Not testing redirects: Test your redirects on a staging site before launch. One wrong redirect file can break everything.
Forgetting to update canonicals: Make sure canonical tags on your new site point to the new URLs, not the old ones.

How long does it take to recover rankings?

If you do the migration right, you might see a small dip in rankings for 1–2 weeks while Google recrawls and reindexes your site. Then things stabilize.

If you mess it up (no redirects, broken pages, thin content), recovery can take months—or you might never fully recover.

What to do next

If you're planning a migration, don't wing it. Make a checklist, map your URLs, set up redirects, and test everything before launch.

If you want help planning or executing a migration without losing traffic, reach out here or get a free audit to identify risks.

FAQ

Can I migrate my site in phases (a few pages at a time)?

Yes, but it's more complicated. You'll need to maintain two versions of your site simultaneously and carefully manage which URLs are live. For most small businesses, a full cutover migration (old site off, new site on) is simpler and safer.

What if I didn't set up redirects and already launched?

Fix it now. Map your old URLs to new URLs, set up 301 redirects, and submit your updated sitemap to Google Search Console. The sooner you fix it, the less damage. Some rankings may recover, but you'll likely lose some traffic permanently.