How to Update PHP Version in WordPress (Without Breaking Your Site)

That yellow “PHP Update Recommended” notice in your WordPress dashboard isn’t nagging for the sake of it. It means your site is running on an engine that is slower than it needs to be, and possibly one that no longer gets security patches at all. Learning how to update the PHP version in WordPress takes about ten minutes, and the switch itself is a single dropdown in your hosting panel. The part that matters is everything you do around that click.

This guide covers how to check your current PHP version, which version to pick in late 2026, how to test the change without risking your live site, and how to roll back in seconds if something breaks.

What Is PHP and Why Does Your WordPress Version Matter?

PHP is the programming language WordPress is written in, and your web server runs a specific PHP version to execute it. Newer PHP versions are faster and still receive security fixes, while old versions are frozen and exposed. Updating PHP is a server change, not a WordPress change, so it does not touch your content, theme settings, or database.

Every page load on a WordPress site runs through PHP: the theme, every active plugin, WooCommerce, the admin dashboard. When the PHP version underneath is outdated, the whole stack inherits its problems.

According to the official PHP project, each PHP branch gets two years of active support and then two more years of security-only fixes. After those four years, the branch reaches end of life and stops receiving patches entirely. A WordPress site on an end-of-life PHP version can have every plugin fully updated and still sit on top of a runtime with known, unpatched vulnerabilities.

How Do I Check My Current PHP Version in WordPress?

Go to Tools > Site Health in your WordPress dashboard, open the Info tab, and expand the Server section. The PHP version is listed there. Your hosting control panel shows the same number, usually under a setting called PHP Selector, MultiPHP Manager, or PHP Settings.

While you’re in Site Health, check the Status tab too. WordPress Site Health flags an outdated PHP version as a recommended improvement or a critical issue depending on how old it is.

If you have WP-CLI access over SSH, this works as well:

wp --info
# or, without WP-CLI:
php -v

One catch: php -v on the command line can report a different PHP version than the one serving your website, because many hosts run separate PHP versions for CLI and web requests. Site Health is the more reliable number for the website itself.

Which PHP Version Is Best for WordPress in 2026?

PHP 8.4 is the best default for most WordPress sites in late 2026. WordPress.org officially recommends PHP 8.3 or greater, and WordPress 6.8 and later are documented as fully supporting PHP 8.4. PHP 8.4 also has active support until December 2028, which gives you the longest runway without pushing onto the newest branch.

Here’s how the current PHP versions stack up, based on the official PHP supported versions table and the WordPress core team’s spring 2026 PHP support clarification:

A strong opinion here: don’t upgrade to PHP 8.2 in late 2026. PHP 8.2 loses security support at the end of this year, so moving to it means doing this whole process again in a few months. If you’re upgrading anyway, skip ahead to PHP 8.3 at minimum.

PHP 8.5 is a perfectly valid choice too. The WordPress core team documents WordPress 6.9 and 7.0 as fully supporting PHP 8.5. The risk with the newest PHP version is rarely WordPress core; it’s the older or abandoned plugin that hasn’t been tested against it yet.

Is It Safe to Update PHP on a WordPress Site?

Updating PHP on a WordPress site is safe as long as you take a backup first, test the new version on a staging copy, and know how to switch back. The PHP update itself does not delete or change any content. The only real risk is an outdated plugin or theme that uses code the newer PHP version no longer allows, which shows up as an error or a broken feature.

Here’s the uncomfortable truth most guides skip: a site that “can’t” move off an old PHP version is usually being held back by one plugin. That plugin is often abandoned, and an abandoned plugin is a security problem whether you update PHP or not. The PHP upgrade just makes the problem visible.

How to Update the PHP Version in WordPress: Step by Step

To update the PHP version in WordPress, back up the site, update WordPress core, plugins, and theme, switch PHP on a staging copy and test it, then change the PHP version for the live site in your hosting control panel and watch the error log for a day or two. The full process is below.

Step 1: Take a full backup

Back up both the files and the database, and store the backup somewhere other than the same server. A PHP switch is easy to reverse on its own, but a backup covers the scenario where something writes bad data while the site is half-broken.

Step 2: Update WordPress core, plugins, and theme first

Plugin and theme developers ship PHP 8 compatibility fixes in their regular updates. Upgrading PHP while running two-year-old plugin versions is how a ten-minute job turns into an afternoon of debugging. Get everything current first, then change PHP.

While you’re on the Plugins screen, look for anything that hasn’t been updated in over a year. Those are your most likely failure points, so note them for testing.

Step 3: Test the new PHP version on staging

Create a staging copy of the site, switch only the staging copy to the new PHP version, and click through everything that matters. If you don’t have one yet, this guide on how to create a WordPress staging site walks through the setup.

Turn on debug logging in the staging site’s wp-config.php so PHP warnings get written to a file instead of shown to visitors:

define( 'WP_DEBUG', true );
define( 'WP_DEBUG_LOG', true );
define( 'WP_DEBUG_DISPLAY', false );

Errors will land in wp-content/debug.log. Then test:

• The homepage, a blog post, and your most important landing pages
• Contact forms (submit one for real)
• WooCommerce cart and checkout, if the site sells anything
• Logging in, saving a post, and uploading an image in wp-admin
• Page builder editing (Elementor, Divi, Bricks) if you use one

Deprecation notices in the debug log are warnings, not failures. They tell you a plugin needs an update eventually. Fatal errors are the real stop signs.

Step 4: Change the PHP version on the live site

You cannot change the PHP version from inside the WordPress dashboard. PHP runs on the server, so the switch lives in your hosting control panel. Where to find it depends on the host:

• cPanel: Software > MultiPHP Manager, or “Select PHP Version” on CloudLinux servers. Tick the domain, pick the version, apply.
• Plesk: Websites & Domains > your domain > PHP Settings (or the PHP version shown under the domain).
• Custom hosting dashboards: Usually under the site’s settings, labelled PHP version, PHP engine, or server settings.
• VPS or self-managed server: Install the new PHP-FPM package with the same extensions you run now, then point the web server at it.

After switching, clear every cache layer: the caching plugin, server cache, any CDN, and OPcache if your host exposes a button for it. Then reload Site Health and confirm the new PHP version shows up.

Step 5: Monitor for 48 hours

Some PHP errors only appear when a specific feature runs: a scheduled email, a cron job, a payment webhook. Keep an eye on the server error log and the site for a day or two after the PHP update before calling the job done.

What to Do If Your Site Breaks After a PHP Update

If your WordPress site breaks after a PHP update, switch back to the previous PHP version in your hosting panel first. That restores the site within a minute or two in most cases. Then find the plugin or theme causing the error on staging, update or replace it, and try the PHP upgrade again.

Roll back first, debug second. There’s no reason to troubleshoot on a live site while customers watch an error page.

Common symptoms after a PHP version change include a white screen, the “There has been a critical error on this website” message, or a WordPress 500 internal server error. In almost every case, the debug log names the exact file that failed. If the file path points into wp-content/plugins/, the folder name tells you which plugin to blame. If it’s less obvious, the process for finding which WordPress plugin is causing a problem applies here as well.

Once you’ve found the culprit, there are three options: update it, replace it with a maintained alternative, or ask the developer for a PHP 8 compatible version. Staying on an end-of-life PHP version to protect one abandoned plugin is the wrong trade.

Does Updating PHP Make WordPress Faster?

Updating PHP usually makes WordPress faster, especially when jumping from PHP 7.x to PHP 8.x, because newer PHP versions execute the same code more efficiently. The gain shows up mostly in uncached requests: wp-admin, WooCommerce cart and checkout, logged-in users, and search pages.

Don’t expect a PHP update to fix a slow site on its own, though. If your homepage is already served from a page cache, PHP barely runs for that request. Heavy images, bloated page builders, and slow hosting will still be slow on PHP 8.4. Think of the PHP upgrade as free performance you collect while fixing a security problem, not as a speed optimization strategy.

The Bottom Line

If Site Health says your PHP version is outdated, believe it. Back up, update everything, test PHP 8.4 (or 8.3 at minimum) on staging, then flip the switch in your hosting panel. The whole job takes less time than recovering a site that got hacked through an unpatched runtime, and if anything goes wrong, rolling back is one dropdown away.

Frequently Asked Questions