An SEO Agency’s Guide To Avoiding Website Migration Disasters

Keira Lorimer October 1, 2025

A website migration usually involves a drastic change during the process of moving a website from one place on the internet to another. This change could come in the form of a domain change or a switch to a new CMS. Whatever the reason for the change, a migration can often result in a sudden drop in traffic. As an SEO agency that has handled countless migrations, we understand the challenges that come with a website migration. Fortunately, we know how to handle these challenges to avoid permanent drops in traffic. Read on to see how you can migrate your website without losing any SEO benefits.

Reasons For Losing Traffic After A Migration

Indexing Issues

Your website could contain the most persuasive, well-written content that the world has ever seen, but it becomes rather pointless if it isn’t being indexed. If you’re new to SEO, indexing refers to the process that occurs between Google crawling your content and ranking it. Here’s a more detailed breakdown.

Google’s army of robots trawls the web looking for webpages and content, which they discover by hopping from one webpage to another through internal and external links. Once Google finds your page, it will attempt to analyse the content of the page in a process called indexing. After a webpage has been indexed, Google can work out the order in which webpages should appear for certain search terms. However, just because a website or page can be crawled doesn’t mean it can be indexed. Without your content being indexed, it won’t show up on Google’s SERPs, which could explain why your website has lost SEO value after a migration.

There are a few methods you can use to check if Google is indexing your content.  

• Google ‘site:’ Search

The quickest way to check if a webpage has been indexed by Google is to carry out a quick Google search. Search ‘site:’ followed by the webpage URL. If your webpage appears, your website is being correctly indexed by Google.

• Google Search Console

Another way is to use Google’s suite of troubleshooting tools. If you have Google Search Console set up for your website, you should find an indexing report in the overview section. This allows you to see how many pages are not being indexed, which pages aren’t being indexed and also the reason preventing each page from being indexed by Google. 

• Screaming Frog

There are other third-party tools that can also help you get to the bottom of your indexing issues. Screaming Frog allows you to analyse a range of SEO factors for all pages across a certain URL, which can be extremely beneficial if your website migration involves domain or URL changes. 

It’s worth pointing out that indexing a new website or new content can take time, and your indexing issues may just be a case of waiting. You can speed the process up by requesting indexing in Google Search Console, but expect indexing to take between a few days and a few weeks depending on the size and structure of your website.

Incorrect/Missing Redirects 

If you’re migrating to a new domain or URL, installing redirects are one of, if not the most important part of a website migration. Without this, users will be sent to a page that no longer exists, causing them to see a 404 message and causing your website’s traffic to tank.

All old URLs should use a 301 redirect to the most relevant new URL. A 301 redirect tells Google that this is a permanent change, allowing link equity to be shifted from the old URL to the new one. Once again, you can check for 404 errors caused by broken links using Google Search Console or third-party tools like Screaming Frog.

Algorithm Updates or External Factors

The biggest impact on your organic traffic could be external, and to some extent, out of your control. Ensuring your content aligns with Google’s algorithm is undoubtedly the aim of the game when it comes to SEO, so it’s important to keep on top of any changes.

If any changes occur to your website’s aesthetics or content during a migration, this could easily be the cause of any SEO falloffs. If you’re working with an agency during a website migration, it’s vital that they understand SEO. Examples of common mistakes include removing optimised content for “better looking” content, altering heading structures or focusing on the look of a website without considering the impact on performance.

If you are about to partner with an agency to design a new website for your business, it’s worth asking whether or not they intend for the new designs to be JavaScript-heavy, and how they intend to render the website if so. Websites that are heavy on JavaScript are more difficult to read from Google’s perspective if they haven’t been rendered correctly.

If you have experienced a sudden loss in traffic and/or rankings post migration, it could be that your agency has prioritised aesthetics before SEO. 

Website Migration SEO Checklist

Preparation

• Compile a list of all current site URLs 
• Compile a list of all new URLs
• Create a redirect list mapping old URLs to the most relevant new URLs

Migration

• Ensure any test site has a ‘noindex’ tag and a ‘nofollow’ tag to prevent duplicate content
• Crawl and check the new website for broken internal links
• Ensure all meta titles and descriptions have been carried over to the new website
• Implement the 301 redirects 
• Ensure the redirects are working effectively using Screaming Frog crawler
• Remove the blocker rule in the HTML to allow the new site to be crawled
• Upload the new XML sitemap into Search Console and verify
• Prompt to index the rendered site on both desktop and smartphone

Monitoring

• Check Google Search Console for crawl errors 
• Take a daily reading of rankings and compare to pre-migration baselines

Final Thoughts

If you’ve recently experienced a drop in traffic after a website migration, the good news is that most drops are recoverable. There are a few things you can do to immediately identify the problem, such as ensuring pages are being indexed and checking if redirects have been implemented. If the right steps have been taken in these areas, it could be that your new website simply isn’t optimised for SEO purposes. 

If you’re considering a website migration and want to preserve SEO rankings, or you’re struggling to recover lost traffic after a poorly executed migration, feel free to contact us, and we’ll see how we can help.