Ultimate Guide to Website Migrations

In this instalment of our Ultimate Guide series our authors are looking at Website Migrations. At Tea Time SEO, Sara Moccand-Sayegh, Ben Beckwith and James Bavington, shared their Website Migrations tips which they have expanded on in this Guide. Covering three aspects of Website Migrations:

  • Planning and Strategy
  • Site Consolidations
  • Launch Day Priorities

Every site migration comes with its own challenges but with the help of this guide you should be able to prepare effectively and take the precautions you need to ensure a smooth transition as possible.

Chapter 1 - Planning and Strategy from start to finish

In a migration, planning and having a strategy is equally important as knowing what you need to do from a technical point of view. Planning can be even more crucial in a large organization where the developer team is often not in the same location as the project manager/project owner responsible for the website. For this reason, the ideal situation is for an SEO to be included from the beginning of the project. 

Below are 5 tips that will help SEOs better plan their migration: 

Tip 1: Plan your migration based on the project plan (where possible)

If an SEO is involved in a migration, there is a good chance that this is because it’s a complex website migration which implies a new server, CMS, design, content and URLs. In a perfect world, you would migrate one step at a time, but most of the time, everything happens at once. That’s why it’s important to plan as much as possible to minimize the risk. It’s not just the SEO who needs to plan, but also the person responsible for the new website. This will result in a project planning (see image below).

By looking at the planning, an SEO can see when developers are working on a project and define when the SEO jobs cross the developers’ work. The two most crucial moments in the project planning are the tech set-up and the go-live. 

  1. Tech set-up: If an SEO wants to influence the technology or define some basic requirements, they should do so when the tech set-up discussions are still open. Once the tech set-up is defined, it’s difficult to change it. The tech set-up, as said before, could imply requirements such as asking for server-side rendering for JavaScript framework such as Vue.js or more basic requirements such as ensuring that the client can write their own title tags if they wish. For example, if you use Contentful (which is not a CMS) to ensure that a client can write their own title tags, you need a bit of development. 
  2. Go-live: There are some obvious reasons that explain why it’s important to know when a website goes live, such as knowing when the job needs to be delivered. Nevertheless, there are some less obvious reasons, such as knowing when it’s the right time to test everything with developers and knowing when it’s possible to ask for some more changes. The closer developers and POs/project managers are to the go-live, the more they feel the pressure and less time they will probably dedicate to SEO issues. That’s why it’s important to test everything in advance and not on the day before the go-live. 

While the two previous steps are fundamental for an SEO, it’s also important to plan when to test. The more tests done on the staging website, the less the risk of discovering a problem during the go-live. Some things such as the redirection map need to be tested with the support of the development team, so it’s important to also plan the dependencies.

Tip 2: Make sure you know which devs are on the project

Whenever an SEO starts working on a project, the first thing to do is to know who the developers are and what their specialization is (front/back). 

This is important for several reasons: 

  1. When an SEO migrates a website, they will open several tickets for the devs. If developers know the SEO and know why the SEO opened a ticket, then they will help push the ticket and implement it. 
  2. During the migration, SEOs may have an “uh-oh” moment, and sometimes that can happen in the days after migrating the website. As a result, SEOs need to act as fast as possible to correct the problem and for SEOs, the people who can make the difference between success and failure are devs. Developers will have many other problems to fix the days after the migration so their time is extremely precious. Nevertheless, if the SEO responsible has a good relationship with the devs, they will probably work extra hours to help the SEOs fix the problem.

Tip 3: Plan your go-live in a period with low traffic

Migrating a website comes with the risk of losing traffic for a certain amount of time (1-2 weeks). If it’s over a month, then it’s highly possible that it’s a definitive loss of traffic. As a result, it’s a good idea to not migrate the website during a high-traffic period. For example, an e-commerce website that sells luxury watches should not migrate around Christmas (October-December).

Tip 4: Break down your migration into 4 steps

When migrating a website there are a lot of things to do and the best thing is to have an Excel spreadsheet or any other support with all the tasks listed. To make sure that everything is done at the right time, it’s even better to break down the Excel into the 4 migration steps and define the task for each of these steps: 

  • Preparation, 
  • Test in staging, 
  • Go-live, 
  • Follow-up after go-live

The image below shows a visual example of how an SEO could break down the steps.

Tip 5: Before defining the destination URL in the redirection map, wait to have the staging URL

SEO wishes to redirect and the final destination URLs. The risk is that SEOs rush too early in defining the destination URLs and as a result, they need to change them again.

Part of the planning is to decide when the final destination URLs should be defined. If they are defined too early without having them on staging and just by “deduction”, there are two risks that SEOs could encounter: 

  1. It’s not uncommon that the content team does not redefine the content and the new URLs until 2 weeks before the go-live. 
  2. Some CMS have special rules for the URLs. For example, Drupal by default will eliminate all articles. 
  1. It’s not uncommon that the content team does not redefine the content and the new URLs until 2 weeks before the go-live. 
  2. Some CMS have special rules for the URLs. For example, Drupal by default will eliminate all articles. 

Chapter 2 - Site Consolidations/Mergers

Managing a full website migration through to completion, whilst mitigating any significant decreases in traffic and visibility, is an exceptionally complex task. When it comes to website consolidation/merger projects, a lot of the tasks undertaken will be the same as for a typical website migration however there are a few key tasks that need to be considered and prioritised. 

At Semetrical, we undertake a number of website migration projects a year and recently have been spending a lot of time supporting clients with large scale website consolation projects. The 7 tips discussed below have underpinned our successful approach to these types of migrations. They include:

Tip 1: Audit all websites involved in the project

Tip 2: Find the corresponding URLs & missing pages between websites involved

Tip 3: Decide which URLs do not need to be migrated

Tip 4: Signpost to users why they are being redirected

Tip 5: Build a page to rank for branded search queries of the merged sites

Tip 6: Identify keywords gaps between the old URL and the new URLs 

Tip 7: Have patience when the website merger goes live

1. Audit all websites involved in the project

In the pre migration phase of a merger or consolidation project, you should undertake audits of all of the websites involved, This includes the parent website (the website which all other domains will be merged into), alongside auditing the other domains that will be migrated. 

Audit the parent & migrated domains: 

You want to make sure that the main domain has strong technical foundations. This will be  the domain that search engines will be reviewing once all websites have been merged so it is really important to undertake a thorough technical audit of the parent domain. The main areas of review should be identifying and fixing:

  • Crawlability issues, such as a poor crawl path
  • Duplication of URLs, such as duplication content or parameter based issues
  • Speed issues, such as slow server response times
  • Web vital scores to make sure the domain is future proofed
  • Bugs that the developers are not aware of

The migrated domains should also be audited to ensure that no technical issues are migrated across to the parent domain and crawlability issues are addressed. These audits do not need to be as in depth as the parent domain review but it is good to know what issues you are dealing with when merging multiple sites.

Historical penalty analysis

When merging websites, some of the  websites you are dealing with could have historically had a penalty which has caused a traffic drop. If you merge these websites into the new parent domain, those penalties could be transferred across, so it is important to review the Search Console accounts of these websites to see if there has ever been a penalty. In addition to this, we also recommend reviewing historical traffic trends in Google Analytics and third party tools to see if any significant traffic drops align with updates.

Disavow file analysis

It is important to identify all of the disavow files that are present across all of the domains and cross reference the migrated websites’ disavow files to the parent’s. When undertaking this analysis you are ideally looking to identify domains that are not included on the parent domain’s disavow file but are included on the other websites’.

Once you have identified the domains that are missing, combine them with the pre-existing disavow file and re-submit it in Google Search Console.

Once you have merged domains, low quality links that pointed to the other domains will now be pointing to the parent domain, so updating the disavow file will make sure Google will dissociate those low quality links with the new parent domain.

2. Finding the corresponding URLs & Identifying missing pages

In the pre-migration phase of the project you will need to identify the URLs that can be mapped 1 to 1 where similar content exists on the parent domain. This is a critical step and can be quite time consuming. At Semetrical, we will usually map URLs from one site structure to another by:

Matching on URL structures

The end path of a URL can be the same from one website to the other. This is especially common when merging websites in the publication space where a lot of the content can be syndicated. For example, the elements highlighted in red are the same from one site to the other:



Matching on heading and title tags

The H1s or title tags of a page can be the same or very similar from one site to the other, for example:

<title>NHS chief confirms staff were promised higher pay rise</title>

Matching URLs ranking for the same keywords on page 1

If you are struggling to match on URL structures or metadata then matching on keyword rankings can be super useful. For example, if you download a search query report from Search Console along with URLs and cross reference the search query reports from website A and website B you can isolate the keywords where both sites are ranking on page one.

Once you have isolated the cross over of search queries, you then can identify the URL ranking for site A and the URL ranking for site B. The end result is a list of URLs that can be mapped to each other.

Matching using a similarity web crawler tool

A similarity web crawler can be your answer if you are struggling to map URLs to a relevant alternative destination when merging one website into another. At Semetrical, we have built our own similarity tool which can crawl two sites in full and group URLs together based on how similar the page content is. For example, if you set the  similarity score to 85%, the crawl report will only show you the URLs grouped together that are 85% or higher in similarity..

There are other crawling software out there that have a similarity feature built-in which can do something very similar.

There will however be many situations where it is not possible to map a URL from one site to another. In this situation you should identify the pages that cannot be 1 to 1 redirected and provide a list of pages to be recreated on the new website to your development team, along with information on where it should be housed in the website hierarchy.

3. Not all URLs need to be migrated

A website merger gives you the opportunity to clean up content and remove redundant or low quality pages so you don’t have to migrate every page over. Instead you can 404 or 410 these pages.  The criteria to use when evaluating whether  a URL should be migrated over or not includes:

  • Has the URL received consistent traffic in the past 12 – 18 months?
  • Has the URL generated enough traffic that it’s a priority? 
  • Has the URL built up authoritative backlinks? 
  • Has the URL received seasonal traffic spikes?
  • Has the URL been deemed a priority to the business?

If the answer is NO to all of the above then most likely the URL does not need to be prioritised and migrated over and instead can be killed off.

4. Signpost to users why they are redirected

When merging one site into another it is really important that you are considering the user journey to ensure that your customers don’t have a “Where the hell am I?” moment! If a customer goes to site B but lands on site A it could be very confusing and disorientating for them, especially if it is not clear  why this has happened. Below are a few ways in preventing this happening:

  • Create a JavaScript overlay when a user is redirected – this is great for mergers but also when you are rebranding
  • Add a message on-page to say “content was originally from X”

5. Rank for for branded search queries of the merged sites

Make sure the new website is still visible for the old site’s branded keywords as customers will still search for the branded keywords of the sites that have been merged into the parent domain. It is also important to monitor the branded keywords and SERPs of these websites for a period of time following the merger. A couple of ways to stay visible include:

  • Writing an article optimised for the old brand
  • Building an optimised category or hub page for the brand
  • Setting up paid ads to indicate the original site has now moved to a new site

6. Identify keyword gaps between the old URL and the new URLs

When mapping URLs from one website to another they should be mapped and redirected to an equivalent page. However, there can be scenarios where you have a similar URL on both websites, which is great for 1 to 1 mappings, but the URL on site B is performing better than the equivalent URL on site A which is going to be the primary URL after the merger.

The URL on site B could be ranking for a wider range of keywords compared to the equivalent URL on site A, which could mean a drop in traffic following the merging of these two URLs as site A`s URL is not optimised for the other keywords.

To counteract this, once you have finalised the 1 to 1 mappings, you can undertake gap analysis between the two URLs to isolate those missing keywords which can then power a re-optimisation project as part of the migration.

The main steps to take to isolate those missing keywords include:

  1. Take a Search Console report which includes both keyword and URL ranking for each website
  2. Take your URL mapping document and bring in the keywords for both URLs (URL A and URL B)
  3. Compare the keywords ranking for URL A to URL B  and isolate the missing keywords
  4. Make sure you optimise URL B with the missing keywords that URL A ranked for

For more information on the keyword gap analysis process Semetrical have written a blog post on identifying keyword gaps between the URLs being mapped.

7. Having patience when the website merger goes live

Once you flip the switch on the website mergers and the redirects are live, it is absolutely essential that you  have patience and don’t make any rash decisions.

John Muller in 2020 mentioned that when merging websites it can take longer for Google to process all of the changes compared to a typical website migration.

The old website which has now been merged into the parent domain can stay in the Google index for a while post migration, so it can be normal to see both domains appearing on the SERPS for a period of time.

Do not attempt any quick fixes to remove the old domain from the search results as this will just hinder the success of the migration. For example, do not request the domain to be removed in Search Console or keep the old robots.txt file live with a “Disallow: / “ rule.

Chapter 3 - Launch Day Priorities and Ownership

Whether re-platforming, changing domains or overseeing a website consolidation, the launch itself is a culmination of hard work, planning and collaboration between all of those involved in the project. Whether you’re in-house, agency-side or a consultant – James has prepared four key tips that he believes can help any SEO or Project Manager working on a website migration.

StrategiQ is a full-service agency providing both website development and marketing services to our clients as part of an integrated service. One advantage that this gives is the ability to work together on client website migrations allowing the roll-out of a new and enhanced website whilst also leveraging new SEO potential off the back of a successful site migration or launch.

Here’s a summary of the top ‘Migration Launch-Day’ tips:

Tip 1: Earn your relationship with the developers

Tip 2: Distinguish roles and accountability 

Tip 3: Develop a stoic launch checklist

Tip 4: Layer with a custom launch checklist for external collaborations

Tip 1: Earn your relationship with the developers

Having spent ten years as a hands-on frontend developer, James can’t stress enough the value of building and earning your relationships with project developers and engineers. Whilst some developers are curious about and understand SEO, it’s fair to say that many are still understanding the true potential and facets of how their work can be enhanced through the lens of SEO. Early on in the project, share the opportunities that you identify with the team so that they can be factored into the project specification and sprints from the outset. 

Articulating the value of an SEO-related task can also be effective. For example if you’re pushing for faster load speeds, sharing information such as the rumoured Web Core Vitals becoming a ranking signal in May can not only emphasise value from an algorithmic perspective but you could layer this with real-world examples and data of how performance improves user-experience and conversion.  

Developers are problem solvers and can love challenges that utilise their existing skills but give them a chance to learn new things, try out new code and build something effective that they’ve not done before. Present the objective and encourage their ownership of the solution. Ask them how they would go about achieving the objective and enable them to solve the problem rather than telling them how they should go about it.

Building your relationship with a development team, whether for just a few short weeks or over the course of months and even years, comes down to collaboration, trust and respect. If you earn the relationship over time, you’ll develop a strong reciprocal relationship where your input is heard and implemented rather than being perceived as an inconvenience.

There’s hundreds of other fantastic tips and experiences on the above tweet by John Mu which I’d highly recommend checking out.

Tip 2. Distinguish roles and accountability

During the live Tea Time SEO session, Sara raised the importance of planning for any website migration project. When it comes to the days just before (and launch day itself) it’s incredibly important to clearly define roles and accountability between all of those involved and hands-on with the website migration.

A website launch at our agency will almost always typically involve the following four individuals on our team as a minimum:

  • Account Director and/or Project Manager
  • Lead Developer
  • QA Analyst
  • Lead Technical SEO

And even for inter-agency/in-house collaborations there is usually more people and more roles too. Therefore, from the outset it’s important to clearly and visibly agree who is doing what and when. If as the SEO or Project Lead, you delegate tasks to others, don’t assume they’re going to be done – ensure and verify that they have or will be done. This early planning throughout a project pays huge dividends on Launch Day itself because it allows you to stay in-control of your own priorities rather than discovering something you thought was being handled – actually isn’t.

Discuss with the team an effective communications strategy for launch day itself. James has seen challenging and complex sites launches (which can often require the full attention and focus of the development team) hindered by an over-eager SEO or QA colleague flooding Slack with questions and distractions mid-launch which are actually under control. Collaborate on a launch checklist and feedback system that allows you to record and prioritise observations in sprints – so that you can more clearly prioritise tickets and observations for the developers in an effective manner.

Tip 3. Develop a stoic launch Checklist

After watching Tim Ferriss’ Ted Talk on ‘Defining your fears not your goals’ a few years ago – one tip that has always stayed with James is the process of writing lists – allowing him and his team to plan and mitigate what can go wrong in a website launch or migration. This process lends itself well in preparing a core ‘Website Launch Checklist’ that you can build up individually or with your team to note down common issues, checks or actions required for a site launch/migration. 

Having initially started theirs in Trello, then Google Sheets and then back to Trello again – they’ve settled over the past year in building a centralised inter-department launch checklist within Process Street.

This animation above highlights the clean user-interface of Process Street’s checklist style application that allows different teams to collaborate on Master Checklists that we can roll-out for each new project we’re working on. The whole while, key authors from each team are continually tweaking and updating it to ensure it aligns with best-practice or new issues that may have caught us out for the first time. Examples of items for your checklist might be:

  • Dev: Ensuring that the Meta Robots tag isn’t set to noindex,nofollow after launch.
  • SEO: Submitting fresh XML Sitemaps in Google Search Console
  • PM: Ensuring that realtime data is coming through in Google Analytics
  • QA: Checking that caching and other performance metrics are working

The beauty of having a Master Checklist with tools like Process Street, Trello or Google Sheets is that you can:

  • Refine, evolve and continually develop your Master List over time
  • Create variants or Add-ons for specific platforms like Ecommerce
  • Collaborate and delegate tasks to other teams from one checklist
  • Concentrate on the niches and priorities of your work on the migration, knowing that you have a reference of the common, consistent actions or checks to perform.

Tip 4. Layer with a custom Launch Checklist for external collaborations

Building on from Tip 3 is the more tailored approach in creating a launch checklist for external collaborations. In-house or personal checklists are fantastic, but they are typically alien to external collaborators who are either unfamiliar with your tried and tested format or just need something specific and tailored to them rather than the whole project.

When we’re working on a site migration with another agency whereby maybe we’ve built and they’re leading the SEO, or if we’re consulting on SEO for an in-house development team – we typically opt to create an ‘External Checklist’ that is built out with key points and actions from our Internal Checklist. Collaborations shouldn’t be a barrier for utilising and organising your tasks within a checklist.

Introduce and agree the format early with the whole team, rather than pushing something on everyone mid-project or in the run-up to launch. Format isn’t really essential as even at the start of this year, we’ve worked on SEO Launch checklists in both Trello and Google Sheets. What matters is simplicity, clear delegation and prioritisation for a single point of reference for the whole team.

In the example above, you’ll see a custom Google Sheets format that we build out from scratch for a project collaboration whereby we’re advising an engineering team on a replatforming project.

Tasks, status, priority and ownership is clear and central in a single, visible place for all involved in the platforms build and launch. All of the consulting, audits and recommendations provided in the early stages of the project are simply referenced here for checks to ensure their readiness ahead of launch.

In order to succeed in a website migration, SEOs need to have a solid plan right from the moment they get involved. However, having a solid plan without the support of devs is not enough.

Solid planning, support from developers and technical knowledge of how to migrate a website need to go hand in hand in order to succeed.

If you’re planning a website migration this year – then good luck.  Don’t be afraid to ask for advice and a helping hand in ‘The Optimisers‘ – a community of fellow search engine optimisation pros helping each other on the journey to the top of the search engines”.

Next Steps

Learn more tips and advice for website migrations from industry experts on our blog.

Try Authoritas for free today and get started strategising your website migration today.

Or, get in touch with our team and see how our tools can make your migration even smoother!

About the Co-Authors

Sara Moccand-Sayegh

SEO specialist at Liip

Sara Moccand-Sayegh is an SEO specialist at Liip, a web & mobile development agency and Holacracy in Switzerland. She is the co-host of #SEOnerdSwitzerland Meetup and a big fan of taking technical classes but skipping the theory.

Ben Beckwith

Head of SEO at Semetrical.

Ben Beckwith joined Semetrical back in 2014 as one of the first employees and has since grown with the company where he is now Head of SEO. He has developed an award-winning department of SEO specialists at Semetrical and is passionate about all things SEO.

James Bavington

Technical Director at StrategiQ

James Bavington is Technical Director at full-service agency StrategiQ who are based in both Warwickshire and Suffolk UK. James started his career in 2006 as a designer and front-end developer, gaining an affinity for SEO and Ecommerce prior to joining StrategiQ in 2015 to own the cohesion between the development and marketing teams.