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In every website’s life cycle, there comes a time for change. Most of the time, we make small improvements here and there. But every once in a while, we get the idea to change the entire theme. In theory, it is a great move: everything looks much better and your readers love it. However, what is on the surface does not always reveal the technicalities hidden underneath. If your website depends on search engines for a large portion of its traffic, you might be curious as to whether changing your theme will affect your SEO rankings. We are here to answer just that.
As a general rule, your WordPress theme can affect your SEO rankings to a large degree. Themes can impact factors important for SEO, such as your website’s stability, speed, content, metadata, and indexation. However, when done correctly, changing themes can maintain or even improve your SEO rankings.
By changing a website’s theme, all of these factors can be influenced both positively and negatively. You might improve some features while reducing the effectiveness of others. You need a concrete process because of the potential impact these factors can have on your rankings. John Mueller from Google has previously emphasized that testing and maintaining best practices during transitions is vital for search stability.
If we isolate these factors, we can better determine exactly how they affect your website. After an extensive talk with one of our developers, I summarized precisely how that happens.
How does changing WordPress themes affect SEO?
For most people, a WordPress theme is simply a reskin of their pages. However, at its core, a theme can change many essential background details. Many of these details play a role in how Google crawls and perceives your pages. The factors listed below can influence your SEO both positively and negatively when changing your website theme.
9 SEO factors your WordPress theme can affect
1. Increase or decrease your site load speed
Your theme dictates how many scripts and assets your website loads when a visitor arrives. Because of that, changing your existing theme can either speed up or slow down your website. According to benchmarks from WP Rocket, poorly coded or bloated themes can significantly slow down performance.
As a rule of thumb, you should aim for a theme that is as fast as possible out-of-the-box. That is because once you implement a theme, your plugins and customizations will further increase the page load time. Speed impacts your Core Web Vitals, which are confirmed ranking signals in Google’s algorithm. In some extreme cases, there could even be incompatibilities that make the new theme significantly slower than your current one.
There is some excellent research available here, where they compare how fast each theme loads.
2. Improve or worsen your design & user experience
Your WordPress theme, of course, controls one of the most critical modern website factors: your design. Naturally, using a theme that satisfies you makes the experience more enjoyable – and work does not feel like work. Design elements directly influence engagement metrics like bounce rate and dwell time.
However, website design is even more critical from the point of view of your users. User experience is crucial for your conversion rates and SEO; therefore, a theme might either improve or ruin it. Modern standards like the W3C WCAG 2.2 guidelines also suggest that accessibility is part of a high-quality user experience.
In almost all instances, when changing an existing website’s theme, users are initially confused until they get used to it. While that is subjective and hard to judge upfront, search engines notice if users quickly leave your site due to poor navigation.
But there are also many objective factors that you can use to judge a theme before deciding on it. I find this topic exciting and recommend that you familiarize yourself with it if you are running a website. Here is updated UX guidance from NN/g that I highly recommend.
3. Secretly modify your SEO metadata
Your theme can also affect how robots like Google see your site. That is because different themes can contain or edit additional metadata that Google uses to understand your page better. Matt Cutts, former head of webspam at Google, once advised that theme changes should be handled cautiously to avoid technical pitfalls like broken links.
SEO metadata like the page title and meta description are not direct ranking factors – meaning they alone will not determine where you rank. However, they are indirect factors that influence a user’s decision on whether to click on your website. Professional audits often show that keeping consistent metadata is key during a redesign.
If you currently rank high for a target keyword, changing that page title even by accident can cost you rankings in the long term. To learn more about the effects of changing page titles on SEO, read this post.
4. Add, change, or remove structured data
Similar to the point above, different themes bring different structured data setups. Structured data, also known as Schema, is a type of metadata that search engines like Google use to better understand a page’s content. Industry experts at Digital Scouts highlight how essential technical factors like schema are for visibility in 2025.
If your current theme marks all your articles with the proper Schema, you could potentially lose that by changing the theme. Structured data itself is not a make-or-break ranking factor. However, like many things in SEO, it is a piece of the puzzle that can give you a slight boost.
5. Impact the site search functionality
Some themes can remove your site search functionality. Before implementing a new one, ensure everything works. If you are currently using a search bar, check if the new theme supports it, too. In contrast, if you are not currently using one, implementing it alongside your new theme is an excellent idea.
Doing this will allow users to navigate your site more effectively and help you track what visitors are interested in through Site Search Tracking. Besides that, site search functionality can be extended, which some themes can also affect.
For example, by default, when users look for information through the search bar on your site, WordPress checks post titles and content for matches. However, some themes can add functionality to scan other elements, which can return irrelevant results. This can negatively impact the user experience if people find what they are looking for.
6. Change your content formatting (e.g., headings)
Different themes can also impact the format of essential HTML elements. One common occurrence is duplicate heading tags. While this is not a make-or-break issue, it can confuse both Google and the reader, as both expect a proper hierarchy of elements. Proper headings are also a core part of Section 508 accessibility standards.
This can be an issue if, for example, your current theme requires you to add H1 tags manually. New themes might have that functionality built-in, meaning you will have to revisit old pages to remove redundant elements. You can see whether you have missed or duplicated headers using our SEO checker tool.
7. Good themes use native WordPress functionality
If you are deciding on a theme, you likely want to explore the functionalities it offers. While you do not have to be a technical specialist, it is good to keep in mind that high-quality modern themes use native WordPress functionality. This is preferable to having too many custom-built features.
Anything custom-built can break when WordPress updates its core functionalities. However, if the theme uses native functionality, the chances of that happening are much lower because WordPress developers ensure their own features work.
Similarly, the functionality of some themes might conflict with specific plugins. While everything might work great at first, custom functionality increases the risk of errors in future updates. This applies to changes in the WordPress core, the theme itself, and the plugins you are using.
8. Single-purpose themes are often better
If your WordPress site has a specific use case (e.g., it is a blog and you do not sell products), pick a single-purpose theme. Multi-purpose themes come with extended functionalities to cover all use cases, which can bloat your website. Excessive scripts can damage your performance metrics.
In turn, this can be confusing when looking at the dashboard. Additionally, it can unnecessarily increase the load time of your pages. To learn more about niche vs. multi-purpose WordPress themes, check out this breakdown.
9. Modify default image sizes and their indexation
One area your theme can influence from a content perspective is your images. By default, WordPress creates different versions of your image upon upload to allow you to use the best size for the job.
For example, you do not need to load a full-size HD image on your blog archive page. Doing so will only slow down your website. Instead, WordPress shrinks the images, making them much lighter for users to download. Faster sites are easier for search engines to crawl, as noted in Google’s performance guidance.
However, some themes can change the default processing for images. While it is unlikely that your new theme will replace the photos in your blog posts, there is a chance it could happen. If that occurs, you could lose your Image SEO and alt tags. Additionally, it can make your posts less relevant overall, which can hurt your SEO.
This is all great, but I would not want to leave you with only this information. Having changed themes myself in the past, I have summarized a quick checklist of tips to help you move forward.
Naturally, some of the factors above are more important to monitor than others. In the table below, you can see the importance of each element. They are scored based on their severity and the likelihood of becoming an issue.
| Factor | Likelihood | Severity |
|---|---|---|
| Change in page load speed | 4 | 4 |
| Change in design & UX | 5 | 5 |
| Change in SEO metadata | 2 | 4 |
| Change in structured data | 4 | 3 |
| Change in site search functionality | 1 | 1 |
| Change in content formatting | 5 | 2 |
| Errors with custom functions | 3 | 5 |
| Theme bloat | 3 | 3 |
| Change in image size and indexation | 2 | 2 |
| Important SEO factors to monitor when changing WordPress themes (1 Low; 5 High) | ||
Are WordPress themes good or bad for SEO?
As a general rule, WordPress themes are not inherently bad for SEO. Your theme allows your content to be displayed in a unique way, which can improve the user experience and your branding. However, some WordPress themes are less optimized for SEO than others, making them a suboptimal choice.
Many themes are created by developers without previous SEO experience or an understanding of the industry. This is usually the case with older themes that are not regularly maintained or updated. Expert reports from Semrush suggest that while temporary ranking drops can happen, sites often recover with the right optimizations.
Badly developed themes can also contain security holes that hackers can exploit. This is especially true for themes that are not regularly updated. Running outdated versions of a theme can also force you to stick to a particular version of the WordPress core because of compatibility issues, providing even more ground for potential exploits by malicious parties.
By using a theme that is not optimized for search engines, you can lose important content. Many themes feature custom functionality that is often not carried over when implementing a change. From a search engine perspective, this could mean that your pages are suddenly much less relevant to searchers because they no longer provide the same quality of information. Content relevance is a critical ranking factor for Google.
Additionally, depending on the coding, themes can slow down your site and create a less pleasant experience for visitors. The standards for website speeds are getting higher as the internet evolves, as do the requirements from search engines like Google. Slow websites that create a bad user experience can cause your rankings to plummet, even if your content remains intact.
Meanwhile, many modern themes are particularly optimized for SEO while still providing a good visual experience. We will not feature a comprehensive list in this post, but we recommend this list by AIOSEO, which contains an in-depth breakdown of many major WordPress themes.
11 helpful SEO tips before changing your WordPress theme
Before committing to such a large change, it is crucial to have a process to ensure everything goes smoothly. Knowing this will help you prepare beforehand and avoid hurting your SEO. Many issues can arise if we are not careful, as changing themes is often when we decide to perform a cleanup on our sites.
To prepare your website before changing your theme:
Choose an SEO-friendly theme carefully
As explained, changing your theme can strongly influence your website’s performance. If you decide to take such an important step, ensure that you are at least matching the SEO performance of your current theme. Ideally, your new theme should be even better and more SEO-friendly.
Reduce plugin usage with a functional theme
This builds upon the previous point but spans even broader. Finding a WordPress theme that has many features yet is well-optimized is critical. It will save you from using unnecessary plugins, which are often the most significant factors influencing the speed and performance of a WordPress site.
The fewer plugins you use, the fewer requests will be made, leading to lower load times and a better user experience. Read more about HTTP requests here.
Get a very fast theme if using a page builder
Whether you are using Elementor, Divi, or any other page builder, you need to understand how they work. Themes load specific scripts and assets by default that are necessary for the theme to function correctly.
When building a page with a tool like Elementor, the page builder brings many additional assets and scripts with it, too. However, most WordPress sites do not come with an out-of-the-box way to limit which scripts get loaded where. This means that regardless of whether the assets are shown, they might still be loaded by the browser.
Therefore, if you decide to build your website to your liking, remember to get a lightweight theme that does not include too many options by default. This can save your users crucial loading time. Leading figures like Brian Dean stress that speed optimization is non-negotiable during these transitions.
While Google won’t necessarily reward you just for great load times, their site speed guidelines are a standard that will hurt you if you do not meet them.
Do not change your theme too often
Your theme can impact if and how your pages get indexed by Google. Changing a theme also influences the user experience. Constant changes bring many unknowns and potential errors. If you cannot handle them promptly before Google re-crawls your website, it will hurt your site’s reputation in Google’s eyes.
Additionally, with the rollout of Google’s Core Web Vitals as a ranking signal, you are putting more on the line. Google uses performance data from extended periods to determine whether your website is well-optimized. Therefore, changing your themes often can impact that data and cause you to lose rankings.
Crawl your website before and after the change
Getting a report of all your pages is a best practice for maintaining site health. While you should do that regularly, it is especially important during big changes. Rand Fishkin has often recommended detailed performance audits whenever major site changes occur.
Use a tool to get a list of all existing errors on your site before and after changing themes. This way, you can compare the two sheets to see what you have solved and what new problems have appeared.
Some crawlers will help you get this right from a technical perspective (scripts, HTML response codes, etc.). If you are looking for a technical crawler, I strongly recommend Screaming Frog. Regarding that, here’s a deep-dive guide for 2025 – and as the name suggests, you can do almost anything with the tool.
Others focus more on the SEO aspect, checking for things like broken images or links, titles and headings, and SEO metadata. Morningscore, the tool we developed, specializes in helping with such performance checks.
Map out how you will deliver Schema markup
Depending on your current setup, how you add Schema to your pages might change. Some themes have that functionality built-in, while others do not. If you are adding Schema through a plugin, check if there are any conflicts between the two.
Double-check both external and installed scripts
Some people deliver third-party scripts through plugins, while others add scripts like Schema or Google Tag Manager directly.
Changing a theme can change what scripts run when a visitor comes to your site. In turn, this can break functionalities or skew your analytics reporting.
Ensure your URLs are perfectly remapped
When changing themes, we often look at the overall structure of our sites. This process frequently goes hand in hand with editing categories and cleaning up URLs. This can be done by using an SEO friendly URL checker.
But since this is no small change, you can easily overlook some things by accident. Therefore, ensure that you redirect any URLs you edit to their new addresses.
Here is a simple plugin that I love for setting up redirects in WordPress.
Create your site in a test environment first
As with any serious update, it is best to implement the new theme in a development environment first. This is a copy of your website that runs on your local machine. When updated, this site does not change your live website’s content, allowing you to test exactly how things will change.
Here is an excellent guide on how you can set that up yourself.
Speak with someone who has done it before
Lastly, here is a more human tip. Changing a theme is no small task, even though it only takes the click of a button. The best advice I can give you is to talk to someone who has done it before. Like every significant change, you run the risk of mistakes.
If you know a developer, give them a call. If you do not know anyone in the space, search online. Many companies will provide useful tips out of professional courtesy. Even if you have to pay for a consultation, it can save you a ton of trouble.
Diligently check Google Search Console data
Your Google Search Console contains invaluable information. It is the only real source where you can see exactly how Google perceives your website. The two most essential tools you need to know are the “Coverage” and “Crawl Stats” tabs.
Learning how to work with them will ensure you see potential errors as soon as possible. This is especially important after making massive changes where many URLs can be affected simultaneously.
Should you change your WordPress theme?
In the end, changing your theme can have huge potential upsides, but it can also drastically hurt your SEO rankings and traffic. Because of that, the only way to answer the question is:
To judge that, you need to answer:
What is the main reason: Do you want to change your theme just because you “like it better”? If so, what are the odds you won’t prefer another theme a month later? Alternatively, is there a functional reason for the change?
For example, this could be because your current theme is suboptimal in some aspects (e.g., page speed, bad design). Do you genuinely believe users will like the new theme better?
How old is your website: If you want to change the theme on a brand-new website with little to no traffic, the answer is most often yes. You are not putting much on the line, and changing the theme later will have a much more significant impact than doing it now.
In contrast, if you have an established website, changing the theme can cause your rankings to dip temporarily (or permanently if done incorrectly).
Can you handle complications: If something goes wrong, do you have the technical knowledge to roll it back? Alternatively, do you have the resources to pay someone who can help?
No matter what you choose, I strongly recommend you check your keyword rank in Google and set up tracking before you change your theme. This way, you can monitor every single change in rankings, which will help you understand if anything went wrong or if you need to take action.
Changing themes without losing your content and SEO efforts
Regardless of what you have decided, I strongly recommend reading through a couple of checklists that can guide you. This will ensure you have the basic knowledge needed to prepare the site before and after the update.
In turn, this can save you from losing your SEO progress when implementing significant improvements. Here are two resources from WPBeginner that I advise reading before you implement the new theme: Checklist & Guide.
Lastly, I leave you with one of my favorite experts in the WordPress community. This video by Adam Preiser from WPCrafter goes into great detail on how to safely change your WordPress theme.
FAQ
How can one effectively measure the SEO impact of changing a WordPress theme over time? Are there specific tools or metrics recommended for this purpose?
Measuring the SEO impact of changing a WordPress theme over time involves using analytics tools like Google Analytics to monitor traffic and engagement metrics before and after the change. Tools like Google Search Console can help track site performance, keyword rankings, and indexing issues, providing insights into your SEO health.
Can changing a WordPress theme have a different impact on SEO depending on the type of website (e.g., e-commerce vs. blog) or its size and traffic volume?
The impact of changing a WordPress theme on SEO may vary by website type and size. E-commerce sites, for instance, might experience different effects due to their complex structures and functionalities compared to simpler blogs. It is crucial to consider specific SEO needs based on your website’s characteristics.
How does the process of changing themes interact with other SEO strategies, such as content optimization and link building? Is there a recommended sequence of steps to follow when undertaking multiple SEO tasks simultaneously?
Integrating theme changes with other SEO strategies requires a holistic approach. Optimizing content and building links should be continuous efforts, whereas changing a theme is less frequent. Prioritize maintaining SEO fundamentals like site speed, mobile responsiveness, and user experience throughout all tasks. Ensuring a smooth transition without disrupting these elements can help mitigate potential negative impacts on SEO.
