Changing the PHP version in Plesk is one of the quickest ways to resolve website compatibility issues, improve performance, or prepare an application for a newer release. If your site runs on WordPress, Joomla, Laravel, Drupal, Magento, or a custom PHP application, the PHP version used by the domain can affect everything from page loading to plugin behavior and error messages.
In Plesk, PHP can usually be changed per domain, which makes it easier to test compatibility without affecting the rest of your hosting account. This is especially useful on managed hosting plans where different websites may need different PHP versions.
When to change the PHP version in Plesk
You may need to update or switch the PHP version if you see errors such as blank pages, “500 Internal Server Error,” deprecated function warnings, or plugin and theme incompatibilities after an application update. A newer PHP version can also provide better speed and security, while an older version may be required temporarily for legacy code.
- Your website or application requires a specific PHP version.
- A plugin, extension, or theme is not compatible with the current PHP version.
- You are moving from an older application stack to a supported PHP release.
- You want to test site behavior before upgrading production.
- You need to align PHP settings with the requirements of your CMS or framework.
Before making any change, it is a good practice to check the official requirements of your application and note the current PHP version and handler used by the domain.
Check the current PHP version for your domain
In Plesk, PHP version is often configured separately for each domain or subdomain. To confirm what is currently active, open the domain settings in the panel and review the PHP section. Depending on your hosting provider’s configuration, you may see the PHP version, the handler type, and additional settings such as memory limit, upload limit, or execution time.
If you are troubleshooting, it is useful to compare the current version with the version required by the application. Many modern websites run best on current supported versions of PHP, but some older websites still depend on specific older releases.
How to change PHP version in Plesk
The exact menu names can vary slightly depending on the Plesk edition and the hosting environment, but the process is usually straightforward.
Step 1: Log in to Plesk
Sign in to your Plesk control panel using your hosting account credentials. If you manage multiple websites, make sure you are in the correct subscription or domain context before making changes.
Step 2: Open the domain settings
From the left menu or the main dashboard, select the domain you want to manage. Then open the hosting settings or the PHP settings section for that domain. On some installations, this may appear under Websites & Domains, then Hosting Settings, or directly under PHP Settings.
Step 3: Find the PHP version selector
Look for a field labeled PHP version, PHP support, or a dropdown list showing the currently active version. In many Plesk installations, you can choose from multiple PHP releases, such as 7.4, 8.0, 8.1, 8.2, or newer versions depending on server support.
Step 4: Select the required version
Choose the version your application needs. If you are upgrading for compatibility, it is usually wise to move in stages and test each major version before making the final switch on a live site.
If you are not sure which version to choose, follow the requirements of your CMS, framework, or vendor documentation. For example, an application may support a range of PHP versions, but perform better on the newest supported stable release.
Step 5: Review PHP handler and settings
In some environments, the PHP version is tied to a handler such as FPM, FastCGI, CGI, or Apache module. If your hosting provider allows it, you may also be able to change the handler type. For most modern hosting platforms, PHP-FPM is often recommended for better performance and resource handling.
At this stage, you can also review related PHP settings:
- memory_limit — useful for larger applications and imports.
- upload_max_filesize — controls file upload size.
- post_max_size — affects form submissions and media uploads.
- max_execution_time — helpful for long-running scripts.
- display_errors — should usually be off on live sites.
Step 6: Apply the changes
Save the updated settings. Plesk may apply the change immediately, though in some hosting environments there can be a short delay while the web server updates the domain configuration.
Step 7: Test the website
After changing the PHP version, load the website in a browser and test key functions such as login pages, forms, checkout flows, search, and media uploads. Check the application logs if anything stops working. If the site uses caching, clear it after the change so you can verify the latest state.
Changing PHP version for multiple domains
If you host several websites in Plesk, you may need to update PHP versions one by one. This is common in shared hosting and managed hosting environments, where different projects have different compatibility requirements.
For websites that share similar codebases, it can be efficient to standardize on a supported version across those domains. Still, always test first, especially if one website depends on a plugin or custom extension that is not yet compatible.
Recommended checks before upgrading PHP
Upgrading PHP can improve security and performance, but compatibility is the main risk. Before switching a live site, review the following points:
- Confirm the application supports the target PHP version.
- Update the CMS core, themes, and plugins/extensions first.
- Create a backup or ensure a restore point is available.
- Test on staging if your hosting plan provides one.
- Check for deprecated functions in custom code.
- Review error logs after the change.
If you manage a WordPress site, outdated plugins are one of the most common reasons a PHP upgrade fails. For custom applications, older functions, syntax, or libraries may need code updates before the new version can run correctly.
How to troubleshoot common problems after changing PHP version
Website shows a 500 error
A 500 error after changing PHP version usually points to incompatibility, a bad handler setting, or a problem in custom code. Revert to the previous PHP version if needed, then inspect logs and disable recently added plugins or extensions one by one.
Site loads but some features stop working
This often indicates partial compatibility. The homepage may work, but forms, payment modules, or admin functions can fail if the application or a plugin uses deprecated PHP functions. Check the error log and update the affected component.
Blank page or white screen
A blank page often means a PHP fatal error is being hidden. Enable error logging temporarily in a safe way, or review the Plesk logs for the domain. Then identify the file or plugin causing the failure.
Changes do not seem to take effect
If the website still behaves as before, clear application cache, browser cache, and any server-side cache available in the hosting panel. Also confirm that you changed the PHP version for the correct domain or subdomain, since Plesk settings can be separate for each site.
PHP version is missing from the list
If the version you need does not appear in the dropdown, it may not be installed or enabled on the server. In managed hosting, this may require assistance from the hosting provider. Some environments only offer versions that are currently supported and maintained.
Best practices for PHP version management in Plesk
For reliable hosting, treat PHP changes as part of your regular maintenance process rather than a one-time task. A planned upgrade is much safer than waiting until the version becomes unsupported.
- Use a supported PHP version whenever possible.
- Test upgrades on staging before changing production sites.
- Keep extensions and applications updated.
- Monitor error logs after each change.
- Document which websites use which PHP version.
- Review compatibility before installing new plugins or modules.
In an EU hosting environment, this is particularly important when multiple websites are operated under the same hosting account across different business sites, because one compatibility issue can affect a customer-facing application or internal tool.
PHP version and performance considerations
Newer PHP versions often offer improved performance, lower memory usage, and better security compared with older releases. For many modern websites, switching from an outdated version to a supported one can reduce server load and improve response times.
However, performance gains only matter if the application remains stable. A site that breaks on a newer PHP version is not ready for production use until compatibility issues are resolved. The safest approach is to balance application support, code quality, and hosting configuration.
FAQ
Can I change PHP version only for one website in Plesk?
Yes. In most Plesk setups, PHP version is set per domain, subdomain, or subscription, depending on how your hosting account is structured.
Will changing PHP version delete my data?
No, changing the PHP version does not delete website files or database content. It only changes the runtime used to execute PHP code. Still, a backup is recommended before any update.
Which PHP version should I choose?
Choose the version supported by your application and compatible with your plugins, extensions, and custom code. When possible, use the newest supported stable release.
What should I do if my site breaks after the change?
Switch back to the previous working PHP version, check the error logs, and review incompatible plugins, extensions, or custom code. If needed, test changes in staging first.
Why does my hosting provider not offer older PHP versions?
Older PHP releases may be removed for security and maintenance reasons. Hosting platforms typically provide supported versions only, which helps protect websites and the shared infrastructure.
Do I need to restart the server after changing PHP version?
Usually no. In Plesk, the change is applied through the control panel and web server configuration without a manual server restart from the user side.
Summary
Changing the PHP version in Plesk is a simple but important hosting task. It helps you keep websites secure, compatible, and efficient. The safest process is to verify the current version, choose a supported alternative, apply the change in the domain’s PHP settings, and test the site carefully afterward.
If a website fails after the switch, the most common causes are outdated plugins, deprecated code, or an unsupported application stack. With a backup, proper testing, and attention to logs, you can manage PHP version changes in Plesk with minimal disruption.