The data on migrations is genuinely sobering, and the gap between a smooth move and a disaster is narrower and more technical than most businesses expect.

Key Takeaways

  • Around 60% of migrations result in measurable organic traffic loss, according to a 2025 Ahrefs analysis.
  • One study of 892 migrations found that the average time to regain pre-migration traffic was 523 days, with 17% never recovering.
  • A complete one-to-one redirect map is the single biggest determinant of the outcome.
  • Benchmark everything before making changes, because recovery cannot be measured without a reliable baseline.
  • Rankings typically begin to erode three to four weeks after launch rather than immediately.

What Counts as a Migration

More projects qualify than people realise, which is part of the problem. A migration is any change to how your site is structured or addressed.

That includes moving to a new domain, changing platform or CMS, restructuring URLs, consolidating multiple sites, moving from HTTP to HTTPS, and full redesigns that alter page addresses.

A visual refresh that keeps every URL intact is not a migration, while a redesign that changes them is.

Domain moves carry the highest risk because you are transferring accumulated authority to an address with no history.

Platform changes come next, since URL patterns usually change even when nobody intended them to.

The Numbers Are Sobering

This is worth stating plainly before anyone books a launch date. A 2025 Ahrefs analysis found roughly 60% of migrations produce measurable organic traffic loss.

Recovery times vary enormously. Google's John Mueller has indicated that ranking stabilisation typically runs four to twelve weeks for a well-executed move, while a study of 892 migrations reported an average of 523 days to fully regain pre-migration traffic, with 17% of sites not recovering within a thousand days.

That spread is the important part. The same project can resolve in three weeks or never resolve at all, and the variable is almost entirely execution rather than luck.

Redirect Mapping Is the Whole Game

If you take one thing from this, take this. Every indexed URL on the old site needs mapping to its closest equivalent on the new one, redirected with a 301.

The failure that causes the most damage is redirecting everything to the new homepage. It feels like a safe catch-all, and it discards URL-level relevance entirely, so the authority a specific page accumulated over years lands nowhere useful.

Chains are the second problem. Each additional hop between old URL and final destination degrades the signal, so redirects should resolve in one step rather than passing through an intermediate address.

Use 301 for permanent moves and reserve 302 or 307 for genuinely temporary changes. A permanent move served with a temporary redirect tells search engines to keep the old URL indexed.

There is also a case for letting some pages go. A retired product redirected to a loosely related category page often performs worse than a clean removal with a helpful message, so mapping should involve editorial judgement rather than a spreadsheet formula.

Benchmark Before You Touch Anything

You cannot prove recovery without knowing where you started, and this step is skipped constantly.

Export twelve months of Search Console data covering clicks, impressions, queries, and average position.

Pull your analytics equivalents for organic sessions and conversions. Then crawl the existing site to produce a complete inventory of every live URL, because you cannot redirect what you have not catalogued.

Record indexed page counts as well. A significant change in that number after launch is one of the earliest signals that something has gone wrong.

The Staging Mistakes That Ship

Two errors account for a striking share of migration disasters, and both are trivially avoidable. The first is launching with the staging noindex tag still in place, which tells search engines to remove your entire site.

The second is canonical tags still pointing at the staging hostname. The new site then tells Google that the authoritative version of every page lives on a URL nobody can reach.

Build on a password-protected, noindexed staging environment, then run a full technical audit there before launch.

Crawling staging and comparing it against your saved crawl of the live site surfaces missing pages while there is still time to fix them.

Add a pre-launch checklist item for both tags specifically. They are the two most expensive lines of code in the project.

Do Not Combine Changes

Migrating and redesigning content at the same time is tempting, and it makes diagnosis nearly impossible. If traffic drops afterwards, you cannot tell whether the cause was the technical move or the new copy.

Sequence them instead. Migrate first, confirm stability, then change content, which costs an extra few weeks and saves a great deal of guesswork.

The same logic applies to metadata. Titles, descriptions, and structured data do not migrate themselves, and they need rebuilding and verifying on the new platform before launch rather than after.

What Happens After Launch

Expect a dip and know what size is normal. A temporary decline of roughly ten to fifteen percent in the first month is common while search engines reprocess your site.

A sustained drop beyond about thirty percent is a signal to investigate rather than wait. Check redirects first, then indexation, then canonical tags.

Timing catches people out. Rankings frequently hold for the first two or three weeks and then erode, because reprocessing takes time, so early calm is not proof of success.

Monitor intensively at first. Daily checks for the first fortnight, weekly through the third month, and keep redirects in place for at least twelve months on a domain move.

For domain changes specifically, submit the Change of Address request in Search Console. It signals the move at the domain level and the transfer period runs for around 180 days.

Do Not Lose Your Backlinks

Redirects carry most of the value from links pointing at old URLs, which is why the map matters so much. They are not a complete substitute for the real thing.

Identify your most valuable referring pages before launch and ask those sites to update the link directly. A handful of updates on high-authority sources is worth the effort, even though the 301 would have handled most of it.

Internal links deserve the same attention and are entirely within your control. Every internal link should point at the new URL rather than relying on a redirect, because a site full of internally redirected links looks careless to a crawler and slows every page.

Do not forget the places outside your site. Email footers, social profiles, ad campaigns, printed material and third-party directory listings all carry URLs that will start bouncing through redirects on launch day.

When to Bring in Help

Small migrations on a handful of pages are manageable in-house with care. Anything involving a domain change, a platform move or more than a few hundred URLs benefits from someone who has done it before.

Engaging a search engine optimisation company such as Spicy Web before the build starts is considerably more useful than calling one after traffic drops.

The redirect map should be built alongside the new site structure rather than reverse-engineered from it in the final week.

Ask any prospective partner how they handle redirect mapping and what their post-launch monitoring cadence looks like.

Specific answers to both indicate someone who has recovered a migration rather than only planned one.

Conclusion

Migrations fail on preparation rather than on technology. The redirect map, the pre-launch benchmark, and the staging checks account for most of the difference between a three-week wobble and a two-year recovery.

Build the map before you build the site, separate the technical move from content changes, and plan monitoring before launch rather than after. None of it is glamorous, and all of it is cheaper than rebuilding an audience.

Website Migration SEO FAQs

What counts as a website migration?

Any change to how your site is structured or addressed, including domain changes, platform moves, URL restructuring, HTTP to HTTPS, and redesigns that alter page addresses.

Do most migrations lose traffic?

A 2025 Ahrefs analysis found around 60% produce measurable organic traffic loss, though well-executed moves recover within weeks.

How long does recovery take?

Four to twelve weeks for a well-executed migration according to Google's John Mueller, though one study of 892 migrations reported an average of 523 days to fully recover.

What is the most common migration mistake?

Redirecting all old URLs to the new homepage instead of mapping each one to its closest equivalent.

Should I use 301 or 302 redirects?

Use 301 for permanent moves. Reserve 302 or 307 for changes that are genuinely temporary.

How much of a traffic dip is normal?

Around ten to fifteen percent in the first month. A sustained drop beyond roughly thirty percent warrants investigation.

When do rankings actually drop?

Often three to four weeks after launch rather than immediately, because search engines take time to reprocess the changes.

How long should redirects stay in place?

At least twelve months for a domain move, and there is rarely a good reason to remove them at all.

Do I need the Change of Address tool?

For domain moves, yes. It signals the change at domain level in Search Console, with a transfer period of around 180 days.

Can I redesign content at the same time?

Better not to. Combining both makes it impossible to diagnose whether a drop came from the technical move or the new content.