How Do I Update or Change My PHP Version

Ultra Web Hosting runs CloudLinux with multiple PHP versions available simultaneously. You can change your PHP version per-domain directly from cPanel using MultiPHP Manager, and the change takes effect immediately with no downtime. This guide covers how to switch versions, when you'd want to, and how to handle compatibility issues.

01. Why Change Your PHP Version

The most common reasons to change PHP versions:

• WordPress or plugin requires a newer version - WordPress 6.x requires PHP 7.4+ and recommends 8.1+. Some plugins and themes set their own minimums. You'll see a dashboard notice if your version is too old
• Performance improvement - PHP 8.x can be 2-3x faster than 7.x for the same code. If your site feels slow, upgrading PHP is one of the easiest performance wins. See our WordPress Performance Guide
• Security - older PHP versions stop receiving security patches. Running an unsupported version exposes your site to known vulnerabilities
• Legacy software compatibility - occasionally you need to downgrade because an older application doesn't work with newer PHP. This is a temporary fix; the real solution is updating the application

02. Check Your Current PHP Version

There are several ways to check which PHP version your site is running:

From cPanel

Log into cPanel and look at the right sidebar. Your current PHP version is displayed in the "General Information" section. This shows the default version for your account.

From WordPress

In your WordPress admin, go to Tools > Site Health > Info > Server. The PHP version is listed there along with other server details.

With a phpinfo File

Create a file called phpinfo.php in your public_html directory with this content:

<?php phpinfo(); ?>

Visit yourdomain.com/phpinfo.php in your browser. The very first line shows the PHP version, and the rest of the page shows all loaded extensions and settings.

03. How to Change PHP Version in cPanel

Ultra Web Hosting uses cPanel's MultiPHP Manager, which lets you set the PHP version for each domain yourself without contacting support.

1. Log into cPanel - go to your hosting control panel
2. Open "MultiPHP Manager" - it's in the Software section. Click it
3. Select the domain - tick the checkbox next to the domain (or subdomain) you want to change. You can select more than one at a time
4. Choose your version - use the "PHP Version" dropdown on the right to pick the version you want. Available versions range from PHP 7.4 through 8.5
5. Click "Apply" - the change takes effect immediately. No server restart or waiting required

04. PHP Extensions

PHP extensions add functionality like database connectivity (mysqli, pdo_mysql), image processing (gd, imagick), encryption (openssl), and more. Each PHP version ships with the common extensions enabled by default, so the vast majority of applications work the moment you set the version.

What's Enabled

• WordPress - mysqli, curl, gd or imagick, mbstring, xml, zip, openssl (all on by default)
• Laravel - all WordPress requirements plus bcmath, ctype, fileinfo, json, tokenizer (all on by default)
• IonCube Loader - available on every version; see our IonCube guide
• Zend Guard Loader - available on supported versions; see our Zend Guard guide

05. Customizing php.ini Settings

You can customize PHP settings like memory limits, upload sizes, and execution time from cPanel without editing files manually.

Via MultiPHP INI Editor

Open MultiPHP INI Editor in the Software section of cPanel, select your domain, and use "Basic Mode" to change the common php.ini directives:

• memory_limit - maximum memory a script can use. Default on our servers is 384MB. Increase if you get "Allowed memory size exhausted" errors
• upload_max_filesize - maximum file upload size. Default varies; increase for large media uploads or plugin imports
• post_max_size - must be equal to or larger than upload_max_filesize
• max_execution_time - how long a script can run before it times out. Default is 30 seconds. Increase for long imports or migrations
• max_input_vars - increase this if you have complex WooCommerce products or large forms that fail to save

For anything not shown in Basic Mode, switch to "Editor Mode" in the same tool to add raw php.ini directives.

Via .htaccess

You can also set PHP values in your .htaccess file. This is useful for per-directory overrides. See our .htaccess guide for syntax details.

php_value memory_limit 512M
php_value upload_max_filesize 64M
php_value post_max_size 64M
php_value max_execution_time 300

06. Which PHP Version Should I Use?

07. Troubleshooting After a Version Change

White Screen or 500 Error After Upgrading

This almost always means a plugin or theme uses syntax that's been removed in the newer PHP version. The fix:

1. Switch back - set PHP back to the version that was working in MultiPHP Manager. Your site will come back immediately
2. Enable debug mode - add WP_DEBUG to wp-config.php, switch PHP forward again, and check the error log for the specific file and function causing the issue
3. Update the offending plugin/theme - most developers have released PHP 8.x compatible updates. If the plugin is abandoned, find an alternative

"Allowed Memory Size Exhausted"

This isn't usually caused by the PHP version change itself, but upgrading PHP can change memory usage patterns. Increase memory_limit in the MultiPHP INI Editor (Section 5 above).

Functions or Extensions Missing

Each PHP version loads the standard extensions by default, so this is rare. If your application reports a missing extension (like ioncube_loader, imagick, or intl) after a version change, open a support ticket with the extension name and the domain and we'll enable it for that version.

"Your PHP Installation Appears to Be Missing the MySQL Extension"

This WordPress error means the mysqli extension isn't active for the selected PHP version. It's enabled by default on every version, so if you see it after a change, open a support ticket and we'll check the configuration for that domain.

Quick Recap: PHP Version in 5 Steps

If you only do 5 things from this guide, do these:

1. Use PHP 8.3+ if your software supports it - it's faster, safer, and uses less memory
2. Change versions in cPanel - MultiPHP Manager > select the domain > choose the version > Apply
3. Test your site immediately - visit every major page and form after the change
4. Adjust php.ini in MultiPHP INI Editor - raise memory_limit or upload sizes there if an app needs more
5. Delete phpinfo.php - never leave it accessible on a live site

Last updated October 2026 · Browse all Hosting Control Panel articles