Website merge: how to avoid losing traffic and rankings

At some point, all website owners face the challenge of updating or migrating their site. On the one hand, it’s exciting to refresh the look and feel of the business online. But on the other hand, merging an old site with a new one can be risky. One mistake could lead to a significant loss of both traffic and rankings that took time to build. To help you avoid that, we’ve written this guide on how to merge and update a site without losing traffic or SEO positions.

A site merger can involve structural changes, a complete move to a new platform, or switching to a new domain.

The main concern when merging sites is URL management because search engines index your site based on its URLs. Let’s take a closer look at different scenarios for website migration and merging.

➊ Changing the structure of the site

If you're changing the structure, for example:

In this case, you'll need to set up manual redirects. This involves creating a table that maps old URLs to new ones and linking them with a 301 redirect.

➋ Migrating to a new CMS with the same structure

Example:

This is a rare scenario, but we’ve seen it happen. The URLs and structure remain the same; only the CMS and design change. Developers can copy the old URLs from the database to the new site, making the transition seamless for users. However, this is a delicate process that not every developer can handle properly.

This type of migration can also include improvements, such as adding new pages and reorganizing the URL structure, potentially increasing traffic and the indexability of the site.

➌ Moving to a new domain

Full domain change example:

This is common when a company changes its name or acquires a more brand-friendly domain. There’s one key rule to follow here:

All URLs must remain the same, but with the new domain.

For example:

A common mistake is to redirect all old URLs to the new homepage:

Before switching domains, make sure to check the reputation of the new domain to avoid inheriting any penalties from search engines.

How to merge domains in Google?

The merging process happens in a few steps:

1. Set up the redirect in the .htaccess file (the specific code will vary for each site, so we won’t include it here).
2. Add the new site to Google Search Console and verify ownership.
3. Set up the redirects.
4. In the Search Console settings for the old site, request an address change, specifying the new domain.
5. Confirm and wait (it usually takes around 14 days).

The switch usually happens faster, in about 3-5 days for large sites. If your site is huge (e.g., 5 million pages), it may take longer—up to 6 months in our experience.

How to check if the domain merge was successful?

We don’t recommend relying on automated tools, as many are unreliable.

We usually check redirects manually using the Redirect Path plugin for key pages to get a clear picture.

Actions to take after the merge:

In addition to setting up redirects, there are a few things to update in your Google services:

1. Google Tag Manager: Update to the new site and adjust the container settings if the domain changes.
2. Google Analytics: Make changes in the resource settings if you’re changing the domain.
3. Google Search Console: Re-verify the resource, since the verification file might be deleted during the migration.
4. Google Ads: Update any URLs that have changed to avoid issues with ad moderation and traffic source tracking in Google Analytics.

Additional checks after merging two sites:

1. XML sitemap: Ensure it’s on the new domain and includes the correct URLs.
2. Robots.txt: Update with the correct sitemap and domain info, especially if you use the Host directive.
3. Last-Modified header: Pages should return the correct date of their last modification. .htaccess file: Remove outdated redirects and only keep relevant ones to prevent the creation of non-existent URLs.
4. "www" redirect: Check how the domain looks and adjust the .htaccess file if necessary.
5. Redirects for non-existent pages from the old domain: We’ve encountered issues where the developer didn’t account for redirects, which caused major problems.
6. 404 pages in Google Search Console: Monitor for new 404 errors and their dynamics over time.
7. These are the basics of merging a website.

We’ve successfully merged over 20 sites, including one with 5 million pages. If you need more help, feel free to contact us!

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