WordPress PHP upgrades that don’t break your plugins

Your host is retiring an old PHP version and you don’t know what will break. We test your theme, plugins and WooCommerce extensions on PHP 8.5 in staging, fix or replace what fails, then switch your live site over safely.

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Tested on staging first
Theme, plugins and WooCommerce
Backup and rollback plan

Why WordPress sites break on a PHP upgrade

WordPress core itself usually copes with new PHP versions. The problems are in everything around it:

Unmaintained plugins that haven’t had an update in years, often still running on hundreds of sites.
Custom and child themes written for PHP 5 or 7, with code in functions.php nobody has looked at since launch.
Page builders and premium plugins stuck on old versions because a licence lapsed.
WooCommerce extensions and payment gateways, where a fatal error stops orders rather than showing a warning.
Bespoke plugins built by a previous agency or freelancer.

When a host switches PHP versions for you, a fatal error in any of these can take the site down, or quietly break checkout, forms or emails while the home page looks fine.

How we upgrade WordPress sites to PHP 8.5

Copy the site to staging on PHP 8.5, with outgoing emails and payments safely disabled.
Scan every theme and plugin with PHPCompatibilityWP and PHPStan, and check each plugin’s maintenance status and supported PHP versions.
Test the journeys that matter: checkout, account pages, forms, search, imports and admin tasks. Errors and deprecations are logged, not hidden.
Fix, update or replace. Custom code is fixed. Plugins are updated where possible, and replaced where they are abandoned.
Switch production once staging is clean, with a backup and a tested way back.

If your host is forcing the upgrade

Many managed WordPress hosts retire old PHP versions on a fixed timetable, sometimes with little notice. If you have a deadline, tell us when you get in touch. The audit shows quickly which plugins and theme files will fail, so you know whether you’re facing an afternoon’s work or a few weeks.

Check where your current version stands on our PHP end-of-life dates page.

Cost

Start with the fixed-price £350 audit: a staging test on PHP 8.5, a compatibility scan of your theme and plugins, and a written list of what to fix, update or replace. Fixes are then a fixed quote. Agencies with many WordPress client sites should see our white-label service.

Frequently asked questions

Which PHP version should my WordPress site run?

A version that still gets security fixes, ideally PHP 8.3 or newer. We usually recommend PHP 8.5, as long as your plugins support it, because it’s supported until the end of 2029.

Will updating PHP break my WordPress site?

It can, if a plugin or theme uses code newer PHP versions have removed. Testing on a staging copy first finds those problems before your visitors do.

One of our plugins is abandoned. What then?

We look for a maintained alternative that does the same job and plan the switch, including data migration if needed. If the plugin is small or custom, fixing its code is sometimes simpler.

Do I need to give you access to my live site?

Not for the audit. A full backup of the files and database (or a staging copy) is enough. We only need production access, agreed in advance, for the final switch-over.