TYPO3 14 upgrade checklist: how to plan your migration

Planning a TYPO3 14 upgrade? This checklist covers requirements, extensions, templates and testing — the steps we follow for a smooth, low-risk migration.

Upgrading to TYPO3 14 is mostly a well-understood process, but a solid plan makes it smooth and low-risk. Here is the checklist we use on real projects.

1. Check the requirements

TYPO3 14 needs PHP 8.3 or 8.4 and Composer 2. Confirm your hosting can provide them and that your database (MariaDB, MySQL 8.0+, PostgreSQL) is supported.

2. Audit your extensions

List every extension and check for a TYPO3 14-compatible version. Core has absorbed several former add-ons over the years, so some extensions can simply be dropped; others need updating or a custom rebuild.

3. Review templates and custom code

Fluid 5 introduces stricter templates, and legacy hooks are gone in favour of PSR-14 events. Custom ViewHelpers, Extbase code (now attribute-based) and TypoScript conditions that relied on removed APIs all need review.

4. Upgrade in a safe environment

Run the upgrade locally first (for example with DDEV): raise extension constraints to ^14, run the upgrade wizards and update the database schema, then work through breaking changes starting with the frontend and Fluid.

5. Test thoroughly

Check the frontend, editor workflows and integrations, and watch the TYPO3 log for deprecations before going live. Keep your URLs and SEO metadata intact to preserve rankings.

Prefer to hand it over? Our TYPO3 upgrade service covers the whole process end to end, and our development team handles any custom work along the way.