You change your PHP version in Plesk via Websites & Domains > PHP Settings, where you select a version from a list of available options and save directly. This is necessary if WordPress, WooCommerce, or other software requires a newer PHP version, or if your site runs slowly on an outdated version. Always test on a staging environment first before going live, as not every plugin or theme is immediately compatible with every PHP version.
Why would you change the PHP version?
PHP is the programming language that powers WordPress, WooCommerce, and most websites. A newer PHP version is usually faster and more secure than an older one, since outdated versions eventually stop receiving security updates. In addition, more and more plugins and themes require a minimum PHP version to function properly. If you’re still running an old version, you’re not only missing out on performance but also risking vulnerabilities that no longer get patched.
Sometimes it’s the other way around: you install an older plugin that doesn’t work with the latest PHP version. In that case, you can temporarily switch back to an earlier version until the plugin is updated.
Changing PHP version in Plesk: step-by-step plan
Changing the PHP version in Plesk involves a few simple steps. Make sure you have a backup beforehand, so you can always fall back on it if something goes wrong.
Create a backup
Go to the backup function in Plesk and first create a full backup of your website and database, so you can restore it if problems arise.
Open PHP settings
Log in to Plesk and go to Websites & Domains. Click on PHP Settings for the relevant domain.
Select the desired version
Select the PHP version you want to use from the dropdown menu and click OK or Apply to implement the change.
Test your website
Visit your website and check the most important pages, forms, and, for a webshop, the checkout process. Also check the WordPress dashboard for any error messages.
Check error logs
Review the error logs in Plesk to see if any new error messages have appeared after the change that require action.
The safe sequence for changing your PHP version.
How do you know if your site is compatible?
Before flipping the switch, you can prevent many problems by checking in advance whether your website is ready for a newer PHP version. WordPress often shows compatibility warnings in the dashboard under Tools > Site Health. Many plugins and themes list which PHP versions are supported on their own page or in the changelog.
Do you have a test environment available? Use it to try out the new version first without affecting visitors. This way you discover errors before they become visible on your live website.
Solving problems after changing
Do you see a white page, error messages, or a broken layout after the change? This is usually because a plugin, theme, or piece of custom code uses outdated PHP functions that no longer exist in the new version. In that case, first revert to the previous PHP version to get the website back online, and then specifically search for the cause by disabling plugins one by one.
If the problem persists, check the error logs in Plesk for specific error messages. These often state exactly which file and which line of code is causing the error, making it much easier to resolve. If you’re unsure whether you can fix this yourself, contact us via the knowledge base and support for help.
Frequently Asked Questions
Which PHP version should I choose?
Preferably choose the newest version supported by your theme and plugins. This generally provides the best performance and security.
Can changing PHP take my website offline?
Only if there’s code running on your site that’s not compatible with the new version. A backup and prior testing prevent unnecessary downtime.
Does this also work for WooCommerce webshops?
Yes, but for a webshop, test the checkout and payment process extra carefully, as more plugins often work together here.
Can I also switch back to an older PHP version?
Yes, in Plesk you can switch back to an earlier PHP version in the same way if that turns out to be necessary.
Conclusion
Changing a PHP version in Plesk is done quickly, but requires careful preparation: create a backup, check compatibility, and thoroughly test your website after the change. This way you benefit from better performance and security without surprises.