How to migrate a website without losing SEO or traffic.

Old addresses stop answering

Search engines, bookmarks, ads, emails and other sites all point at your current addresses. A new site that changes those addresses without redirects sends every one of those visitors to an error page, and search engines slowly drop pages they can no longer reach.

The second cause is content. A redesign that cuts twenty service pages down to five removes the pages that answered specific searches. Move that content, or merge it into a page that answers the same question, before you delete anything.

One row per old URL

Export every URL the old site has: from its sitemap, from Search Console’s pages report and from a crawl. Add the pages that earn traffic or links. Then give each old address one new address, the closest match in meaning, not the home page.

The map is a spreadsheet with two columns, and it is the most important file in the project. Everything else in a migration is carried out from it.

Permanent, on the server, kept a year

Google recommends permanent server side redirects, 301 or 308, and treats the target of a permanent redirect as the page to show. JavaScript redirects are a last resort. Point each old address straight at its final page, because Googlebot follows a limited number of hops and long chains slow everyone down.

Keep the redirects in place for as long as possible. Google’s guidance, updated on 20 August 2026, says generally at least one year, and longer for people who still use old links.

When the domain changes too

If you move to a new domain, verify both the old and the new one in Search Console and use its Change of Address tool after the redirects are live. The tool is for domain and subdomain moves only. A redesign on the same domain, or a switch to https or www, does not need it.

Website migration SEO checklist

Before launch: record clicks and positions for your main pages, export every old URL, write the map, and move or merge the content that ranks. Keep page titles, headings and the answer each page gives unless you are improving them on purpose.

On launch day: switch on the permanent redirects, submit the new sitemap, test a sample of old URLs, and check that no page carries a leftover noindex tag from the staging site. In the weeks after: watch Search Console for 404 errors and pages dropping out, fix the redirect or the content, and compare the same pages each week.

Before and after, on the same pages

Record clicks, impressions and positions for your main pages in Search Console before launch. After launch, crawl the old URLs to confirm each one lands on its new page in a single hop, check that the new pages are indexed, and compare the same pages week by week.

Google notes that old addresses can keep showing in results for a while after a move, and that this is normal. A page that keeps falling needs a look at its redirect and its content. We measure moves this way and report what the numbers show; we do not promise rankings.