To migrate a site without losing rankings or AI citations, map every old URL to its new one, use permanent 301 redirects, keep your content and structure intact, and launch all at once rather than in dribs and drabs. Most traffic disasters after a redesign or domain change are not caused by the new site being worse — they are caused by broken URL continuity that severs the links, authority and citations the old URLs had earned. Migrations are survivable, and often beneficial, when you treat URL preservation as the top priority.
Why migrations lose traffic
Search engines and AI systems attach a page's accumulated trust to its URL. Links point to URLs, indexes store URLs, and AI answers cite URLs. When you change a URL and do not redirect the old one properly, every one of those connections snaps. The page may be identical, but to the outside world it has vanished and a stranger has appeared in its place.
The most common failure modes are: shipping a new URL structure with no redirects, using temporary 302 redirects that never pass authority, redirecting everything to the homepage instead of the matching page, and quietly dropping content or pages that were pulling traffic. Any one of these can cut organic traffic sharply within weeks.
The pre-migration checklist
The work that protects your traffic happens before launch, not after:
- Crawl the old site fully and export every indexable URL. This is your source of truth — you cannot redirect what you have not inventoried.
- Build a one-to-one redirect map from each old URL to its closest new equivalent. Match like for like: the old product page goes to the new product page, not a generic category. This is the single most important artefact of the whole project.
- Record your baseline. Note current rankings, top landing pages, and — increasingly important — which pages get cited by AI assistants and pull referral traffic from them, using the methods in our guide to measuring AI traffic. You cannot tell if you recovered if you never measured where you started.
- Preserve on-page content and structure. A migration is the wrong time to also rewrite everything. Keep titles, headings and body content as close to the original as you can, so the only variable is the URL.
Redirects: get these exactly right
Use 301 (permanent) redirects, not 302. A 301 tells search engines the move is permanent and passes the old page's authority to the new one; a 302 signals a temporary move and holds authority at the old URL, which is not what you want. The distinction, and the other status codes involved, is covered in our guide to HTTP status codes and redirects.
Two rules that catch people out:
- Avoid redirect chains. Old URL A should point directly to final URL C, not A to B to C. Each hop dilutes signal and slows crawlers. If you have redirects from a previous migration, update them to point straight to the new destination.
- Keep old redirects live for at least a year. Crawlers and AI systems revisit on their own schedule. Remove the redirects too soon and any URL that had not yet been recrawled turns into a 404, breaking citations that were about to transfer.
Launch day and after
Launch the whole migration at once during a low-traffic window, not piecemeal over weeks — a half-migrated site with mixed old and new URLs confuses crawlers badly. Immediately after launch, update your XML sitemap to list only the new URLs and resubmit it, following our XML sitemap guide, and make sure your robots.txt and canonical tags all reference the new structure.
Then watch closely. Recheck that every redirect resolves in one hop, monitor crawl errors for unexpected 404s, and use IndexNow or a sitemap ping to nudge crawlers to revisit the new URLs quickly. Expect a short dip while search engines and AI systems reprocess the move; if your redirect map was complete and one-to-one, rankings and citations typically recover within a few weeks. If they do not, the first place to look is almost always a gap in the redirect map — a set of old URLs that got missed.
About to migrate, or just moved and want to confirm nothing broke? Run the free CheckMy.site scanner to check that your new URLs are reachable, redirect cleanly, and are visible to both search and AI crawlers.