CompatNav

How to downgrade PHP for a WordPress site, and when it’s the right move

By CompatNav · Published · Last reviewed · 3 min read

Short answer

You downgrade PHP where you upgraded it: in your hosting control panel, often under “PHP version”, “PHP Selector” or “MultiPHP Manager”, by choosing the version the site ran before. It works at once and doesn’t touch your posts, pages or files. Do it to get a broken site back, as a pause rather than a plan: older PHP versions stop getting security fixes. While the site runs on the old version again, find what broke, fix it, check the rest, and upgrade again.

When downgrading is the right move

  • The site broke right after a PHP upgrade: a critical error, a blank page, a feature that stopped. Switching back is the fastest way to get it working while you find the cause.
  • One plugin you can’t do without fails on the new version, and its fix will take days. Going back buys that time.

When it isn’t

  • To keep running an abandoned plugin for good. The plugin will never be fixed, and the old PHP version stops getting security fixes. Replace the plugin instead.
  • Below PHP 7.4. WordPress 7.0 and later need it, and stop on anything older with “Your server is running PHP version … but WordPress … requires at least ….” (WordPress 7.1.2 source).
  • Below what your plugins require. A plugin whose “Requires PHP” is above your version then shows “This plugin does not work with your version of PHP”, and WordPress stops updating it.

How to switch back

  1. Open your hosting control panel and find the PHP setting. Hosts name it differently: “PHP version”, “PHP Selector”, “MultiPHP Manager”, or a setting per site.
  2. Choose the version the site ran before the upgrade, and save. Not sure which it was? Your host can tell you.
  3. Reload the site: the critical error should be gone.
  4. Can’t find the setting, or the old version is gone? Ask your host. Meanwhile, the email WordPress sends about the error has a link to log in and pause the plugin that stopped: the critical error guide shows both ways.

The switch changes which PHP version runs WordPress’s code, nothing else: your posts, pages, settings and files stay exactly as they were. Checking and changing your PHP version shows where to find the setting.

Then find what broke

With the site back on the old version, you can look calmly:

  • The error message names the file, so the plugin or theme: reading it.
  • A check for the version you tried to move to shows every plugin and theme that will break on it, not just the first one that stopped the site.

CompatNav, a free plugin on wordpress.org, does that on your server: choose the version you tried, and it reports only what changes between the version the site runs now and that one. That is exactly the list of what blocked the upgrade.

And upgrade again

  1. Update, replace or fix each plugin or theme the check marks “Will break”.
  2. Check again until the verdict says “Safe to upgrade”.
  3. Switch PHP up again at a quiet time, and watch the site and its error log for a week.

Don’t stay down for long. PHP 7.4, 8.0 and 8.1 no longer get security fixes, and PHP 8.2 gets them until 31 December 2026 (php.net, end-of-life list). The upgrade checklist puts the whole process on one page.

Key takeaways

  • Switch back in the hosting panel, where you switched up: the site works again at once.
  • A PHP switch doesn’t change your content, database or files.
  • Don’t go below 7.4 (WordPress 7 stops) or below what your plugins require (their updates stop).
  • Downgrading is a pause: PHP 8.1 and older get no security fixes, 8.2’s end on 31 December 2026.
  • On the old version, check your site for the new one: the report shows exactly what blocked the upgrade.

Frequently asked questions

Will I lose anything by downgrading PHP?

No. PHP is the program that runs WordPress’s code; changing its version doesn’t change your posts, pages, settings or files. The site simply runs on the previous version again.

My hosting panel doesn’t show older versions. What now?

Ask your host. Some keep old versions available for a while after an upgrade; some remove them. If yours can’t switch back, pause the plugin that stops the site instead, through the link in WordPress’s email.

How long can I stay on the older version?

As short as you can. Check php.net’s dates: PHP 7.4 to 8.1 no longer get security fixes, and 8.2 gets them until 31 December 2026.

Check your own site before you upgrade

CompatNav is a free WordPress plugin. It reads the code of your plugins and themes on your own server and tells you, in plain words, what will break and what will only show notices on the PHP version you choose. It never changes your code. It can’t see problems that only appear while code runs with real data, so a quick check of your site after the upgrade still matters.

Get CompatNav on wordpress.org How it works

Sources

About the code examples: each output is the real output of the code shown, run with the official PHP builds, without a php.ini, with all errors reported and displayed. Only the file path was replaced by a neutral server path.