Yoast WordPress SEO Bug Creates Duplicate Sitemaps

A sharp-eyed search marketer noticed that Yoast was creating duplicate sitemaps. It’s unknown how long this has been happening, but Yoast’s head of SEO has acknowledged the glitch and notes that Yoast is aware of the issue and says it’s working on a fix.

Once this duplicate sitemap error was detected, checking the SEO plugins revealed that a similar issue was happening to other plugins as well, but it wasn’t endemic to all SEO plugins.

Yoast SEO sitemap error detected

Brenda Malone (@employee) discovered the bug and tweeted to Yoast about it:

Someone from Yoast replied that they knew of the bug and flagged it internally to fix it:

Yoast SEO sitemap

Yoast SEO sitemap feature automatically generates a sitemap for different post types.

Page sitemaps

For example, a site with a Pages sitemap will post a sitemap URL like this:


Publish sitemaps

A site that does not have thousands of posts will have a post sitemap like this:


A site with a large number of posts may have sitemaps that look like this:



Yoast Duplicate sitemap error

What was discovered is that Yoast also creates duplicate sitemaps.

A site with only one sitemap for “Pages” will have the following sitemaps:

Yoast “page” error in sitemaps

The original “Page” sitemap:


Duplicate “Page” sitemaps:



Yoast “posted” an error in the sitemap

A site with only one sitemap for posts will have the following sitemap:

The original “share” sitemap:


Duplicate “publish” sitemaps:



Yoast multiple sitemaps for jobs

A site with multiple post sitemaps shows the error in a different way.

For example, if a site has thousands of posts and requires three sitemaps, their sitemaps might look like this:

Original Posts sitemaps:


But with a bug with the Yoast sitemap, they now have two additional sitemap files that are duplicates of the first sitemap.

So in the example above, this is the first sitemap: /post-sitemap1. xml

These are duplicate sitemaps of the original first sitemap:



The Yoast Sitemap Bug is located on

The error can be seen on any site that uses the Yoast SEO WordPress plugin, including Yoast itself.

These URLs lead to identical Yoast XML sitemaps:

The sitemap error is not limited to Yoast

What’s really weird is that this sitemap error is not specific to Yoast.

A similar error can be found in many other SEO plugins (but not in all of them).

Oddly enough, many SEO components show similar behavior with regards to bugs.

Something to keep in mind is that plugin makers are bound by the WordPress open source license which mandates that WordPress plugins and themes be considered derivative works. This is a long standing issue that was at one point Explained by Matt Mullenweg Same in 2015.

Matt wrote:

“WordPress is under a license called the GPL, which basically says you can do whatever you want with the software, but if you distribute changes or create derivative works, it also has to be under the GPL. Think of it like the Creative Commons Sharealike License.

In the past people weren’t sure if WordPress themes were derivative works and needed to be GPL. In 2009 we got an outside legal opinion that made it clear that PHP in themes should definitely be GPL, and for CSS and images it was optional. Basically everyone in the entire WP community has gone to the GPL, sometimes called 100% GPL, for all the files needed to run their theme (PHP, JS, CSS, artwork). “

So some of the methods for creating a sitemap may themselves be open source and available for all SEO plugin companies to use, and this may explain why the SEO plugins have the same or similar bug as the ones in Yoast.

Sitemap error affects other SEO plugins

This sitemap bug doesn’t only affect Yoast and Rank Math. It also affects other SEO components.

This error is confirmed in the following SEO plugins:

  • Ranking Math SEO plugin
  • SEOPress WordPress SEO Plugin
  • AllineOneSEO WordPress SEO plugin

SEO click

If your SEOPress sitemap for “posts” starts like this:


There are duplicates created on these URLs:


AllineOneSEO WordPress SEO plugin

If your AIOSEO plugin generates this URL for Posts sitemaps:


It also generates the following:


The above also applies to the Rank Math plugin.

WordPress Sitemap Bugs are not everywhere

Brenda Malone researched this issue and shared that some SEO plugins don’t seem to have this error.

The following SEO plugins correctly generate sitemaps:

  • SEO Ultimate PRO WordPress Plugin
  • Slim Seo
  • Squirrly SEO

How big is this problem?

The best SEO practice is to make things easy for the search engines.

The more errors are introduced, the more likely the search engine bots are to start tripping over errors and generating unexpected issues, especially if that problem is complicated by other errors on the site.

The meaning of SEO is search engine optimization. The easier you make it for a search engine to crawl and discover your web pages, the better for your SEO.

Mistakes are the opposite of improvement. The more errors a website generates, the less optimized the website is.

In terms of SEO, an argument can be made to minimize the impact of these errors and say yes, the site can continue to falter and function normally despite these errors.

But mistakes are still the opposite of SEO.

Related Articles

Leave a Reply

Your email address will not be published. Required fields are marked *

Back to top button