PHP is the underlying scripting language that powers WordPress, its themes, plugins, and most of its core functions. Because WordPress relies heavily on PHP, any update made by your hosting provider can significantly influence the performance, security, and stability of your website. While PHP updates are generally beneficial, they can also create unexpected issues if your site isn’t prepared for the change. Understanding how these updates affect your WordPress site helps you stay ahead of potential problems and ensures your website continues running smoothly.

Why Hosting Providers Update PHP

Hosting companies update PHP versions for several reasons: improved performance, stronger security, modern features, and long-term support. Older PHP versions eventually reach their “end of life,” meaning they no longer receive security patches. When this happens, hosts upgrade to keep their servers secure and compliant. These updates not only protect your hosting environment but also help WordPress run faster and more efficiently.

However, because WordPress relies on a complex ecosystem of plugins and themes, PHP updates can introduce compatibility gaps,especially on sites that haven’t been updated in a long time.

How PHP Updates Improve WordPress Performance

Newer PHP versions are dramatically faster than older ones. PHP 8.x, for example, executes code more efficiently than PHP 7.x and performs multiple operations at once using improved internal engines. For WordPress sites, this means quicker page loads, faster backend actions, and better resource usage.

A website running on a modern PHP version often feels noticeably snappier, especially for dynamic sites like e-commerce stores or membership platforms. Hosting providers upgrade PHP with the goal of giving users this performance boost without requiring them to change anything. When your WordPress setup is compatible, you benefit immediately from better speed and overall responsiveness.

Potential Compatibility Issues with Themes and Plugins

The most common downside of a PHP upgrade is plugin or theme incompatibility. Some older or poorly maintained extensions use outdated PHP functions that no longer exist in newer versions. When PHP is upgraded, these functions break, causing error messages, missing features, or even the dreaded “white screen of death.”

This is especially common with themes purchased years ago and never updated, abandoned plugins, or custom-coded features built using older syntax. WordPress core itself is usually compatible with the latest PHP, but third-party extensions may not be. This is why checking your site’s compatibility before a PHP upgrade is crucial.

How PHP Updates Affect Security

A newer PHP version is always more secure. Each release patches vulnerabilities, closes loopholes, and strengthens the language’s resistance to attacks. If your host updates PHP, your site becomes more secure, but only if your themes, plugins, and WordPress core are also updated. Outdated code running on a newer PHP version is a common combination that creates unexpected behavior.

On the positive side, staying on out-of-date PHP versions can expose your site to major security risks. If your hosting provider forces an upgrade, it’s likely because the old version is no longer safe to run.

Database Queries and Deprecated Functions

WordPress uses PHP to generate database queries, process forms, run cron jobs, and interact with plugins. When PHP is updated, some functions are removed or marked as deprecated. If plugins rely on older syntax, database queries may fail, logs may fill up with warnings, or tasks may stop executing.

Although these changes don’t always crash a website outright, they can create slowdowns, random bugs, or backend errors. This is why it’s important to update all parts of your site, not just WordPress itself, to ensure compatibility with modern PHP versions.

Testing Before and After a PHP Upgrade

A PHP update shouldn’t be treated lightly. Before switching versions, you should always test your website in a staging environment or use compatibility plugins that scan for issues. Many modern hosting providers allow you to switch between PHP versions temporarily, giving you a safe way to test without committing permanently.

After the update, browse your website thoroughly, front end and back end, checking contact forms, payment gateways, admin panels, widgets, and custom features. Catching issues early helps avoid downtime or broken pages.

What You Should Do When Your Host Updates PHP

If your hosting provider announces an upcoming PHP upgrade, take advantage of the notice period to update WordPress core, themes, and plugins. Remove anything outdated or unsupported. If you rely on custom code or older premium themes, consider updating them or replacing them entirely.

If the upgrade is already applied and your site breaks, you may need to temporarily downgrade PHP (if the host allows it) and then troubleshoot plugin-by-plugin to find the culprit. Hosting providers can assist, but ultimately the responsibility for theme and plugin compatibility lies with the site owner.

A PHP update from your hosting provider is ultimately a good thing, it keeps your WordPress website fast, secure, and ready for modern features. However, these updates can expose weaknesses in outdated themes, plugins, or custom code. Staying proactive, maintaining your site regularly, and testing before major updates ensures you enjoy all the benefits of newer PHP versions without the unexpected headaches. In the evolving world of WordPress, keeping your site compatible is just as important as keeping your server up to date.