The core items are: a full pre-migration content and URL audit, complete URL mapping including PDFs, correct redirect implementation, preservation of structured data and internal links, and post-launch monitoring of indexation — skipping any one of these is the most common cause of lost search visibility during a migration.
A documented baseline: every current URL, its traffic, rankings and internal links, so there is something concrete to measure the migration against afterward.
Complete URL mapping covering every page and document, including PDFs, which are commonly missed — see how to redirect legacy PDF URLs — correctly implemented redirects with no chains or loops, and preservation of structured data and internal linking.
Close monitoring of indexation and rankings against the baseline for the first weeks, since problems are far easier to fix immediately after launch than months later. See SEO migration for the full process this checklist summarises.
A well-executed migration should lose very little organic visibility, and that dip is usually temporary. A poorly executed one — missing redirects, broken URL mapping, lost metadata — can lose a substantial share of search visibility, sometimes permanently if search engines fail to reassociate the new pages with the old rankings in time.
Common causes include missing or incorrect redirects, changed URL structures without proper mapping, lost or altered page titles and metadata, and technical issues introduced during the switch. See why did traffic drop after migration for the fuller diagnostic list and how to check each one systematically.
With correct redirects and mapping in place from the start, rankings typically stabilise within a few weeks of launch. Recovery from a poorly executed migration, where errors went uncaught for some time, can take considerably longer and sometimes never fully returns to prior levels, which is why catching issues before launch matters more than fixing them after.
Monitor search console data, crawl errors, and organic traffic daily for at least the first few weeks, checking that redirects are resolving correctly and that new pages are being indexed as expected. Catching a mapping error in week one is far easier to fix than discovering it after rankings have already dropped.
Tell us what is moving and we will build the full checklist against your specific site.