SEO migration: maintain your top search engine positions

Avoid losing traffic when moving your website

Many companies lose a lot of their website traffic when transitioning to a new website (website migration) or restructuring their current website. This is disastrous for your findability, even though you have probably already invested a lot of time and energy in it. Besides, it is also unnecessary, because with a thorough SEO migration, you will not lose traffic.

Help with SEO migration

On this page:

seo migration services from agency Onder, with examples of SEO migrations and a SEO migration plan

What is a SEO migration?

The moment you make a lot of structural changes within your website, this also changes the situation for Google. Helping Google understand this situation We call SEO migration. Structural changes and so different types of migrations that fall hereonder are, for example:

  • Changing domain name (from domain.com to domain.co.uk)
  • Change in terms of code and/or design
  • Change of CMS (from WordPress to Magento)
  • Change in URL structure
  • Combinations of the above

What's the risk if you don't help Google make changes?

Let's keep as much as possible to the old

Every SEO specialist ever

The above quote does speak to situations we experience, because just like humans, search engines can't handle change very well either. So if you're going to change your website in terms of situation anyway, you'd better help Google understand this as much as possible. The moment you don't help Google and don't do a SEO migration, your good positions in Google disappear like snow in the sun. For many organisations and brands, the website or webshop is an important onder part of the business and then losing organic traffic hurts the bottom line tremendously.

In terms of visibility, a website migration zonder SEO help looks like this:

seo migration services from agency Onder, with examples of SEO migrations and a SEO migration plan
A website with more than $ 200,000 value in organic traffic that surrenders 70% of its traffic and value after migration
seo migration services from agency Onder, with examples of SEO migrations and a SEO migration plan
More than 13,000 matching search terms to a website. And after the new website went live, a drop to 4,000 matching search terms

The above situations are not uitzonderlijk: we are often approached by organisations that shoot into panic mode a few weeks after going live because organic traffic is gone.

The SEO migration plan: the steps to take in migration

But what is the ideal way to help Google understand your migration? And what steps should you take to do so as a website owner or SEO specialist? We list the steps of the SEO migration plan for you:

Phase 1: preparation and planning (pre-migration)

We always recommend including SEO in the plans for a new website or changing website, but it is not necessarily necessary. Think, for example, about discussing a new structure or taking stock of which content should be brought to the new situation. However, making preparations for a SEO migration is necessary. The onder parts in this preparation and planning phase are:

  • Agreeing a date for going live, preferably in the off-season in terms of website business
  • Doing a comprehensive baseline measurement of search term positions of current search terms
  • Analysing all existing backlinks
  • Performing a comprehensive crawl of the current website with as much input as possible from sources that know URLs from your website (Search Console, Google Analytics, Ahrefs, etc.)
  • Creating a URL summary from the crawl with any SEO value per URL added to it
  • Creating a URL model of the new website + possibly arranging access to a test environment

No website migration is the same, but these are generally the most important steps in this phase. Obviously, it is also very important to make good planning agreements together (website owner, SEO specialist and web builder).

Phase 2: test phase (pre-migration)

This is the phase before going live with the new website or changing website. This phase is about doing everything you can to make sure Google understands as much as possible which page is moving to a new page. The onder parts of this phase are:

  • Creating a redirect file for URLs that change: link old URLs from the URL overview to new URLs from your URL model
  • Adjusting the internal links in the test environment based on URLs that are going to change
  • Auditing the test environment (checking for crawlability and indexability, as well as SEO elements such as text, meta titles, etc.)
  • Fixing a good 404 page
  • Fixing a new XML Sitemap and preferably also an 'old' XML Sitemap containing all the changing old URLs
  • Testing your redirect file in the test environment. Check that all redirects work and point to the correct destination URL
  • Informing other stakeholders. For example, share the redirect file with your Google Ads agency and email marketing/automation agency

Phase 3: going live (post migration)

The moment to press the button has arrived. Time to show everyone your new website! This phase consists of the following onder parts:

  • Agreeing with the entire project team on when to go live (preferably not on a Friday). And whether it will be a soft launch (going live for a selection of users) or hard launch (going live for everyone)
  • Checking Robots.txt and X-robots or Meta robots (noindex, nofollow)
  • Submitting XML Sitemaps in Search Console
  • Crawling all old URLs known from previous crawls
  • Crawling the new website (often we do the above steps in one)
  • Doing a 'Change of Address' in Search Console (only when migrating from domain to domain)

Something goes wrong in all SEO migrations, even those that go completely by the book. It is always important to consider SEO capacity and development capacity at this stage

Phase 4: after going live (post migration)

This phase is strongly related to phase 3 and runs imperceptibly into it. Because apart from the fact that SEO is a continuous process, you can also adjust your SEO migration in this phase. This phase consists of the following onder parts:

  • Fixing (301 redirecting) all 404s that come in from the crawl or in Google Analytics and Search Console
  • Briefing the developer on bugs (technical SEO issues) that come out of the crawls of the live environment
  • Keeping an eye on the Index coverage report in Search Console
  • Monitoring results (rank tracking, Google Analytics, Search Console, etc.)
  • Updating important backlinks if you have contact with the owners of the websites on which they can be found
  • Making a plan on how you will further up the SEO positions after going live

Examples of our SEO migrations from practice

We at Onder do a lot of SEO migrations, from large to small and complicated to uncluttered. We highlight three migrations of recent times

Example 1: Daka

Daka is a chain of sports shops + a fairly large webshop. They specialise in many product groups and are particularly strong in winter sports items. Daka's marketing team knocked on our door to onder support in the webshop migration that was upcoming.

  • Platform migration from Xsarus TableTop to Magento2
  • Many changes in URL structure + a changing product URL structure
  • Redesign + code changes
  • Many URLs: before going live the number was in the tens of thousands

Daka's new situation was so different that Google did struggle with it at first, but after adjusting with technical changes and content additions, we had an upward trend again, just in time for the post pandemic winter sports season of early 2022.

seo migration services from agency Onder, with examples of SEO migrations and a SEO migration plan
The estimate of organic traffic for Daka.nl with going live to the new situation indicated by the pink arrow

Example 2: Industore

Industore is a technical wholesaler with a sizeable webshop. Industore specialises in a number of niche markets and is therefore particularly findable on technical products. Organic traffic is important for Industore.

  • Platform migration from a custom platform to Opencart
  • Few changes in URL structure
  • Code changes and many technical SEO improvements

Industore was also a typical migration by the book: all onder parts were tightly finished by ourselves, Industore and the connected developer. Still, you see a small dip after going live followed by a nice increase in organic visibility.

seo migration services from agency Onder, with examples of SEO migrations and a SEO migration plan
The estimate of organic traffic for Industore.co.uk with again a pink arrow indicating the time of migration

Example 3: Internetvergelijk.nl

Internetvergelijk.nl is a comparison platform for internet, television and telephone subscriptions. The platform relies heavily on organic traffic and was and is highly findable on a variety of search terms that match the target audience's orientation phase.

  • Changes in URL structure during this migration
  • Redesign + layout changes
  • Transition from HTML to JavaScript framework (which we fortunately found out about in time)

The most exciting aspect of migrating Internetvergelijk.nl was the transition from pages in HTML to a JavaScript framework. Fortunately, we were able to test extensively in the test environment with a Prerender solution that still works well. The transition is hardly noticeable in the results, as organic traffic is still rising.

seo migration services from agency Onder, with examples of SEO migrations and a SEO migration plan
The estimate of organic traffic for Internetcomparison.co.uk with the pink arrow around the live

How can we help: our SEO migration services

We see SEO as a craft and the SEO migration service is very much a onder part of that. So we are happy to help you with that. Every website and every situation is different, so no matter how structured we implement migration plans: a SEO migration is tailor-made. We help many customers with SEO migration on the following three variants:

  1. A comprehensive SEO migration plan incl. implementation: we take a lot of work off your hands with this, because we create the redirect files ourselves in this case and are leading when it comes to the migration project
  2. A SEO migration plan based on advice: the focus in this variant is on advice: the executive part lies with you as the client. That we brief exactly what needs to be done, check and deliver extensive output based on crawls is of course beyond dispute
  3. SEO migration after going live: you can also 'clean up debris' after going live. Website owners regularly knock on the door who have lost some of their traffic by not taking SEO migration into account. Retrospectively, through technical changes and content modifications, a lot can still be saved.

Are you new to the world of search engine optimisation or looking to improve your current strategy? Start with our comprehensive SEO check to make sure you're doing all the basics right. For a thorough evaluation of your website, check out our Live SEO analysis and SEO analysis website. If you have questions about specific terms. 

Can we help your organisation with this? Then get in touch with us!

Getting started with a SEO migration yourself: the checklist

We delen graag onze kennis met je. Dus wil je zelf aan de slag met een SEO migratie checklist en ons stappenplan volgen naar eigen inzicht? Download dan de SEO website migratie checklist van Onder. Succes niet gegarandeerd uiteraard 🙂

Marien de Clercq

Projectleider KlantOnline

Radboud University faced a complex challenge this spring: we wanted to largely switch to an entirely new website (new technology and new look-and-feel), but because that cannot be done in one go, we also had to continue using parts of our old website(s) for a considerable period of time. And, of course, we wanted to continue to be found at least as well by the major search engines. During the SEO migration and the many redirects this required, Martijn and his colleagues helped us very well atonder. Despite the fact that we only had a few weeks to get this right, they got the job done to our complete satisfaction, thanks to their expertise, pragmatism, flexibility and the ability to change gear quickly when circumstances changed.

Richard Schenderling

Webshop Manager

Thanks to good analysis and a comprehensive redirect plan from Martijn and his team, we had a flawless replatforming that saw DAKA switch to Magento. The advice to DAKA's content team ensured a better URL structure, category descriptions, meta titles and descriptions. The accessibility and knowledge of Onder is very good and for this reason I can definitely recommend Onder as a SEO partner.

Bart Spronk

Co-founder Finner

In the SEO field, Finner has accumulated quite a lot of knowledge over the years. It was therefore not easy to find a good sparring partner. We certainly found one in Martijn. When migrating to a new domain and website, he helped us excellently. He is substantively strong, honest and a nice person.


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