An SEO site migration, planned before launch day instead of repaired after.

An SEO site migration is the planning and checking that keeps the rankings, links and traffic a website has earned when it moves to a new design, platform, domain or set of page addresses. Google knows your site as a list of addresses, each with its own history. Change the addresses without telling Google where each one went, and that history is left behind.

What counts as a migration

Moving to a new platform, switching domains after a rebrand, merging two company sites after an acquisition and reorganizing the service pages are all migrations, even when they are sold to you as a redesign. The test is whether page addresses, page content or the domain change. New colors and photos on the same pages don’t qualify.

The risk rises with the number of addresses that change at once.

Before launch: the inventory and the redirect map

I start with an inventory of every address on the current site, noting which ones bring in visits and which ones other websites link to. I match each to its closest equivalent on the new site with a permanent redirect, an instruction that forwards both visitors and search engines from the old address to the new one. That list is the redirect map, and it’s the document that decides how a migration goes.

The shortcut to avoid is pointing every old page at the home page. Google tends to treat a redirect to an unrelated page as if the old page had been deleted. Suppose a roofer in Poway has a tile roof repair page that has ranked for years. If the new site has no tile repair page, the redirect has nowhere honest to go, so the content has to be carried over along with the address.

On launch day

I run a checklist against the live site.

1. The development copy’s block on search engines has been removed. This is the most damaging item to miss.
2. Every line of the redirect map works and reaches its target in one step.
3. Titles, headings and body text made it across intact.
4. Menu and in-page links point at the new addresses, not at redirects.
5. Forms, tap-to-call links and call tracking still work.

After that, the wait is for Google to crawl and index the new pages.

What a domain change adds

A new domain means updating every place that points at the old one. That includes the website link on your Google Business Profile, your citations and business listings and your ad landing pages. Google also provides a change of address notice in Search Console for domain moves. The old domain has to stay registered and redirecting for the long term. Letting it lapse after a few months undoes the work.

Measuring before and after

I record rankings on a rank grid, indexed pages and calls before launch, so there’s something to compare against. A migration bundles many changes into one, which is the opposite of how I prefer to work, so the baseline matters more here than anywhere.

Timing matters too. An HVAC company, for example, is better off relaunching in a quiet month than during the first heat wave of summer.

If the launch already happened

A migration that went wrong can often be partly repaired, and sooner is better. If the old site can be reconstructed from backups or archived copies, I rebuild the address list and add the missing redirects. Recovery isn’t certain, and of all the jobs in technical SEO this is the one where prevention costs far less than repair.