How to change the PHP version in Plesk (step by step)
Published on July 10, 2026 7 min read
Want to change the PHP version in Plesk? Pick the right version for speed and security, adjust the settings and roll back safely if your site breaks.
The PHP version of your website has a big say in how fast, secure and reliable your site runs. The good news: you do not need to be a programmer to adjust it. To change the PHP version in Plesk you only need a few clicks, and you can set it separately for each website. This article explains why the right PHP version matters, which version to pick, how to check the version you run now, how to switch in Plesk and what to do if your site stops working after an upgrade.
What is PHP and why does the right version matter?
PHP is the programming language that powers many websites and content management systems (CMSes), including WordPress, Joomla and WooCommerce. The server runs PHP code to build your pages before they reach the visitor. The PHP version you use has a direct effect on three things.
Speed
Each new PHP version is usually faster than the one before it. Newer versions handle more requests per second and use less memory, so your pages load quicker. If you want to go further, read how to speed up your website with caching and compression.
Security
A PHP version only receives security updates for a limited number of years. If your site runs on a version that is "end of life" (no longer supported), no more security patches are released and you take on needless risk. Choosing a supported version is one of the simplest ways to keep your site safe.
Compatibility
CMSes, themes and plugins set requirements for the PHP version. Modern software often needs a recent version, while very old plugins can break on a new one. The right choice is therefore the newest version that all of your software supports.
Which PHP version should you choose?
The rule of thumb is simple: pick the newest stable PHP version that your CMS, theme and plugins support. That way you get the best speed and security without breaking anything. Here is how support looks in July 2026.
| PHP version | Status | Advice |
|---|---|---|
| PHP 8.5 | Newest version, full support | A fine choice, but test your plugins and theme first |
| PHP 8.4 | Full support | A safe, fast default |
| PHP 8.3 | Security updates only | Still usable, but plan an upgrade |
| PHP 8.2 | Security updates only, until the end of 2026 | Upgrade soon |
| PHP 8.1 and older | End of life, no more updates | Upgrade as soon as possible |
Running WordPress? WordPress itself recommends at least PHP 8.3, and your site will run perfectly on PHP 8.4. The very latest version works too, but first check that your plugins and theme already support it. LJPc always keeps the newest PHP versions available, so you can switch over as soon as your software is ready.
Check which PHP version your site runs now
Before you change anything, it helps to know which version you are on. There are three ways to check.
- In Plesk: go to Websites & Domains. The current PHP version is shown next to your domain, for example PHP 8.2.
- In WordPress: go to Tools > Site Health > Info and open the Server section. Your PHP version is listed there.
- With a phpinfo file: create a file that contains only
<?php phpinfo(); ?>, open it in your browser and look for "PHP Version". Delete this file straight away afterwards, because it exposes sensitive server information.
How to change the PHP version in Plesk (step by step)
You set the PHP version per domain or subdomain, so you can choose a different version for each website. Here is how to do it.
- Log in to Plesk. At LJPc you do this with the Log in to Plesk button in your customer portal.
- Go to Websites & Domains and find the domain you want to adjust.
- Click PHP next to that domain (in some views this is labelled PHP Settings). You now see the PHP settings, with the current version at the top.
- Select the version you want from the top drop-down list.
- Leave the handler on the recommended FPM option (usually FPM application served by nginx). It is the fastest choice for most sites.
- Adjust the PHP settings if needed (see the next section).
- Click OK to save the change.
Plesk applies the new version straight away. No restart is needed and your site stays online. Afterwards, refresh your website and click through a few pages to check that everything still works. Pay particular attention to your login page, forms and your CMS dashboard.
Adjust PHP settings: memory_limit, upload_max_filesize and more
On the same PHP page you can change a few commonly used settings. You only need to do this if a plugin or your CMS asks for it, usually through an error message. For each setting you either pick a value from the list or enter your own.
| Setting | What it does | When to raise it |
|---|---|---|
memory_limit | How much working memory a script may use | On the message "Allowed memory size exhausted" |
upload_max_filesize | The maximum size of a single file you upload | When large images or media will not upload |
post_max_size | The maximum size of a full submitted form (must be greater than or equal to upload_max_filesize) | Raise it together with upload_max_filesize |
max_execution_time | How long a script may run, in seconds | On time-outs during imports or backups |
Click OK after making changes. Do not raise values higher than necessary: limits that are too generous can hide problems instead of solving them. If you are unsure which value to use, start small and increase it step by step.
What to do if your site stops working after the upgrade
Sometimes a plugin or theme is not yet ready for a new PHP version. Your site then shows a blank page (the so-called "white screen of death"), an HTTP 500 error or a message about an unsupported function. Do not worry: a PHP change is always reversible.
- Go back to Websites & Domains and click PHP next to the domain again.
- Select the previous PHP version that your site worked on.
- Click OK. Your site now runs as it did before.
Next, find out which plugin or theme causes the problem. Update your software to the latest version, because updates often resolve compatibility issues. For WordPress, our guide explains how to update WordPress safely. Then test again whether you can move to the new version.
| Symptom | Likely cause | Solution |
|---|---|---|
| Blank page or HTTP 500 error | A plugin or theme is not compatible with the new version | Switch back to the previous version and update your plugins and theme |
| Message "requires PHP x.x or higher" | The software needs a newer version instead | Choose a newer PHP version |
| "Allowed memory size exhausted" | The memory_limit is set too low | Raise memory_limit |
| Large uploads fail | upload_max_filesize or post_max_size is set too low | Raise both values |
| Time-out during an import or backup | The max_execution_time is set too low | Raise max_execution_time |
Still stuck? Get in touch with support and we will be glad to help.
Frequently asked questions
Which PHP version should I choose in Plesk?
Choose the newest stable version that your CMS, theme and plugins support. For WordPress that is PHP 8.3 or higher in practice, with PHP 8.4 being a safe and fast choice. Avoid versions that are end of life (PHP 8.1 and older), because they no longer receive security updates.
How do I check which PHP version my website runs?
In Plesk you see the version next to your domain under Websites & Domains. In WordPress you find it under Tools > Site Health > Info in the Server section. You can also use a phpinfo file, but delete it again straight after use.
Will my website go offline when I change the PHP version?
No. Plesk applies the new version immediately without a restart, so your site stays reachable. Even so, it is wise to check your most important pages right after the change.
My site broke after changing the PHP version. What now?
Go back to the PHP settings for the domain and select the previous version that your site worked on. The change is fully reversible. Then update the plugin or theme that caused the problem and try again.
What is the difference between the PHP version and the PHP handler?
The version is the PHP release itself, for example PHP 8.4. The handler determines how the server runs that PHP. For most sites, FPM application served by nginx is the fastest and recommended choice, and you usually do not need to change it.
Can I use different PHP versions for different websites?
Yes. In Plesk you set the PHP version separately for each domain and subdomain. So one site can run on PHP 8.4 while another still uses an older version.