Website migration is moving content to a new domain, a new URL structure or a new system. It is the riskiest intervention in organic traffic, because a mistake makes the company lose rankings built up over years, and the drop shows up within days. The basis of a successful migration is a redirect map: a list of all existing addresses with a one-to-one assignment of the new address, built from the old sitemap, from search engine reports and from analytics for the last year. Redirects must be permanent and must lead to the content-matching page, not bulk-redirected to the homepage. Before going live, record the baseline traffic and ranking figures so you can measure the impact. After going live, monitor indexing errors, load speed and broken links. Returning to the original figures takes several weeks even with a smooth migration.
See also: Website redesign and SEO, Ownership of the website and source code, Digital Assets of a Company.
