By KYN AI Advisory Team — AI implementation specialists, Singapore
A website migration is any change that alters URLs, platform, domain or templates. Each one can drop rankings if a step is skipped. This checklist is the order we follow on our own builds.
What do you inventory before touching anything?
Before design or development starts, collect what Google already knows about the site.
- Every URL with impressions and clicks from Search Console, last 16 months.
- Every URL from the sitemap and from a crawl of the live site, including images and PDFs.
- Backlinks per URL from Search Console's Links report.
- Title, meta description, H1 and word count for each page.
- Schema types present on each page.
- Current Lighthouse scores for the ten most visited pages.
Merge these into one sheet with one row per URL. Mark each row keep, redirect or retire. A page with any impressions or any backlink is never retired. From our own builds: 83 URLs removed in an earlier cleanup were still indexed months later as 404s. The inventory is what finds them.
How do you map old URLs to new ones?
The redirect map is the second column of that sheet.
- Kept pages: same URL, no entry needed. Prefer this for every page that ranks.
- Renamed pages: old URL to new URL, 301. One hop, never a chain.
- Merged pages: each old URL to the single page that now answers the same intent.
- Retired pages: to the closest relevant page, not the home page. A blanket redirect to the home page reads as a soft 404.
- Already-dead URLs: include them. A 404 that has been indexed is still a 404.
Store the map in the repository with the code, so it moves with the site and shows up in review when it changes.
Which schema and meta tags must carry over?
Templates change in a migration and schema is the first thing lost, because it is invisible on the page.
- Organization on the home page, with name, logo, address and contact.
- Article or BlogPosting on every article, with author, dates and image.
- FAQPage wherever a page has a question-and-answer section.
- BreadcrumbList on inner pages.
- Title and meta description per page, carried over exactly for any page that ranks.
- Canonical tags, especially on paginated and filtered pages.
- hreflang on every page of a multilingual site, pointing at each language version and an x-default.
Render the new templates on staging and validate the output. Schema that fails validation is schema that does not exist.
What is a build guard and what should it check?
A build guard is a step in the deploy pipeline that fails the build when something the migration promised to keep has changed. It turns a one-time checklist into a permanent rule.
From our own builds, the guard compares every URL and page title against a committed list. A page cannot be renamed by accident; the list has to be changed, and the change appears in code review. The same step can check:
- Every entry in the redirect map still resolves to a page with a 200 status.
- The sitemap contains every indexable URL and nothing that redirects.
- No page has an empty title or a duplicate title.
- hreflang tags are reciprocal across languages.
One failed build costs ten minutes. One missed URL costs the traffic that URL carried, usually discovered a month later.
What do you watch in Search Console after launch?
Launch day is the start of the measurement, not the end of the project.
- Coverage: watch for new 404s and "crawled, not indexed" pages in the first two weeks.
- Performance: compare clicks and impressions per URL against the inventory sheet, week by week.
- Redirects: confirm old URLs show as redirected, not as errors.
- Core Web Vitals: confirm the new templates pass on mobile.
- Sitemap: resubmit it the day the new site goes live.
From our own builds: a site moved from a builder to Next.js through this checklist kept all 13 of its URLs and showed no change in traffic through the move. The design changed completely. Nothing Google relied on did.
A migration handled by one team, with the inventory, the map, the guard and the launch checks included in the website work rather than bolted on, removes the usual gap between the designer and whoever is blamed for the traffic drop. See website migration done end to end.
Frequently asked questions
Do I need redirects if the URLs stay the same?
No. A kept URL needs nothing. Redirects are only for URLs that change or disappear.
Should I change URLs during a migration to make them cleaner?
Only for pages with no traffic and no backlinks. A cleaner URL does not outweigh a lost ranking.
How long after launch can a drop appear?
Usually within two to four weeks as Google recrawls. Watch Search Console weekly for the first two months.
Checked October 2026.
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