Migrating from Drupal 9 to Drupal 10

on 18 September, 2025

The digital landscape is constantly evolving, and so too is Drupal, one of the most powerful and flexible content management systems (CMS) available. As Drupal development continues to push boundaries, staying current is crucial for maintaining a secure, performant, and feature-rich website. With Drupal 10 now firmly established, the question for many organizations running Drupal 9 is not if to migrate, but how to do so efficiently and effectively.

This comprehensive guide will walk you through every aspect of migrating your Drupal 9 site to Drupal 10. We'll demystify the process, highlight the benefits, address common challenges, and provide actionable insights to ensure a smooth transition. If you’re looking to enhance your digital presence and leverage the latest innovations, understanding the path to Drupal 10 is your first critical step.

Why Make the Leap? The Compelling Case for Drupal 10

Before we delve into the technicalities, let's explore why moving to Drupal 10 is a strategic imperative for any organization committed to robust web presence. Drupal 10 isn't just an incremental update; it represents a significant leap forward in terms of performance, security, developer experience, and user interface.

Enhanced Performance and Scalability

Drupal 10 is built on modern dependencies and boasts numerous performance improvements. From faster page load times to more efficient data processing, your website will simply run better. This translates to a superior user experience, which is a critical factor in today's competitive online environment. Improved performance also means your site can handle higher traffic volumes with greater ease, making it more scalable for future growth.

Robust Security Measures

Security is paramount for any online platform. Drupal has always been known for its enterprise-grade security, and Drupal 10 continues this tradition with even more advanced measures. By migrating, you gain access to the latest security patches, vulnerability fixes, and best practices, safeguarding your data and your users' information. Staying on an outdated version, like Drupal 9 once it reaches end-of-life, exposes your site to unnecessary risks.

A Modernized User Experience with Claro and Olivero

One of the most visible changes in Drupal 10 is the adoption of Claro as the default administrative theme and Olivero as the default front-end theme. Claro offers a sleek, accessible, and intuitive backend experience for content editors and administrators, significantly improving productivity. Olivero, on the other hand, provides a beautiful, modern, and accessible front-end design out-of-the-box, offering a fantastic starting point for any new or migrated site. This focus on user experience, both for site visitors and administrators, is a testament to the ongoing innovation within the Drupal community.

Streamlined Developer Experience

For developers, Drupal 10 offers a more streamlined and enjoyable experience. With updated dependencies like Symfony 6 and PHP 8.1+, developers can leverage the latest tools and features, leading to more efficient development cycles and the creation of more sophisticated functionalities. This evolution makes Drupal development more appealing and productive, ultimately benefiting your organization by enabling faster feature implementation and easier maintenance. If you’re considering to hire drupal developer or work with a specialized drupal development agency, these advancements ensure they’re working with the most efficient tools.

Future-Proofing Your Investment

Drupal 9's end-of-life means that ongoing support, security updates, and new feature development will cease. Migrating to Drupal 10 ensures your website remains on a supported platform, guaranteeing access to future innovations and a vibrant community ecosystem. This future-proofing protects your investment in Drupal and ensures your digital platform remains relevant and competitive for years to come.

Understanding the Migration Path: Drupal 9 to Drupal 10 is an Upgrade, Not a Rebuild

A crucial distinction to grasp is that migrating from Drupal 9 to Drupal 10 is generally considered an upgrade, not a complete rebuild. Unlike major version changes in the past (e.g., Drupal 7 to Drupal 8), where significant architectural shifts required extensive re-engineering, the path from Drupal 9 to Drupal 10 is designed to be much smoother. This is largely due to Drupal's commitment to continuous innovation and predictable release cycles. The core changes primarily involve updating underlying dependencies and removing deprecated code, rather than rewriting fundamental architectural components. This approach significantly reduces the time, effort, and cost associated with the migration.

Key Considerations Before You Begin Your Drupal 10 Journey

Before initiating the migration process, a thorough planning phase is essential. This preparation will minimize potential roadblocks and ensure a successful transition.

1. Audit Your Current Drupal 9 Site

A comprehensive audit of your existing Drupal 9 installation is your starting point. This includes:

Core and Contrib Modules: Identify all installed core modules and contributed modules. Determine which are actively used and essential for your site's functionality.
Custom Modules and Themes: Document any custom modules or themes you’ve developed. These will require specific attention during the migration.
Third-Party Integrations: List all integrations with external services (e.g., payment gateways, CRM, marketing automation tools). Verify their compatibility with Drupal 10.
Content Types, Fields, and Views: While generally stable, it’s good practice to understand the complexity of your content structure.
Server Environment: Check your current server's PHP version, database version, and other requirements against Drupal 10's specifications. Drupal 10 requires PHP 8.1 or higher and will eventually deprecate older database versions.

2. Review Module and Theme Compatibility

This is arguably the most critical step. Many contributed modules and themes will have Drupal 10 compatible versions available.

Drupal Rector: This powerful tool automates many of the code changes required for deprecated API usage. It can significantly reduce manual effort.
Upgrade Status Module: Install and run the Upgrade Status module on your Drupal 9 site. This module provides a detailed report on the compatibility of your installed modules and themes with Drupal 10, highlighting specific issues and suggesting remediation steps.
Project Pages: Visit the project pages of your critical contributed modules on Drupal.org to check their Drupal 10 readiness. Many will already have stable releases or development versions available.
Replacement Strategies: For any modules that don't have a Drupal 10 compatible version, you'll need to identify alternatives or plan for custom development to replicate their functionality. This is where a skilled drupal development agency can be invaluable.

3. Update Custom Code

Any custom modules or themes you’ve built will need to be updated to comply with Drupal 10's API changes and dependency requirements.

Deprecated Code: Drupal 10 removes deprecated code from Drupal 9. You'll need to identify and update any custom code that relies on these deprecated functions or services. The Upgrade Status module and Drupal Rector are excellent tools for this.
Dependency Updates: Ensure your custom modules and themes are compatible with the updated versions of Symfony, PHP, and other libraries that Drupal 10 uses.
Theme Engine: If your custom theme uses a sub-theme of a deprecated base theme, you'll need to update it.

4. Plan Your Testing Strategy

Thorough testing is non-negotiable. Develop a comprehensive testing plan that includes:

Functional Testing: Verify that all core functionalities, custom features, and third-party integrations work as expected.
Content Migration Verification: Ensure all your content, users, and media assets have migrated correctly.
Performance Testing: Compare performance metrics before and after the migration.
User Acceptance Testing (UAT): Involve key stakeholders and end-users to test the site and confirm it meets their requirements.
Security Testing: Conduct security audits to ensure no new vulnerabilities have been introduced.

5. Backup, Backup, Backup!

Before you touch anything, create a full backup of your entire Drupal 9 site – database, files, and codebase. This provides a safety net in case anything goes wrong, allowing you to revert to the previous state.

The Step-by-Step Migration Process: Getting Technical

With your planning complete, it's time to execute the migration. We recommend performing this process in a development or staging environment first, never directly on your live production site.

Step 1: Update Your Drupal 9 Site to the Latest Point Release

Ensure your Drupal 9 site is running the absolute latest version of Drupal 9 (e.g., 9.5.x). This provides the most stable starting point for the migration and ensures you have all the necessary tools and fixes in place.

Step 2: Address Deprecated Code with Upgrade Status and Drupal Rector

Install the Upgrade Status module on your Drupal 9 site.
Navigate to /admin/reports/upgrade-status and run the scan.
Carefully review the report, focusing on modules and themes that are not yet Drupal 10 compatible.
For custom code and contributed modules/themes you maintain, use Drupal Rector. Drupal Rector is a command-line tool that automates the process of fixing deprecated code. It can parse your codebase and automatically apply the necessary changes to make it compatible with Drupal 10. This tool is a significant time-saver for any drupal development task.
Example usage (after installing Composer and Drupal Rector):
```
vendor/bin/rector process web/modules/custom --config vendor/drupal/rector/rector.php
```
This command will analyze your custom modules and apply appropriate fixes.

Step 3: Update Contributed Modules and Themes

For modules and themes that have Drupal 10 compatible versions:
Composer: Use Composer to update them. If a stable Drupal 10 version is available, Composer will handle the update.
```
composer require 'drupal/module_name:^3.0' # (Replace 3.0 with the D10 compatible version)
```
Remove Incompatible Modules: For modules that are truly incompatible and have no replacement, you might need to disable and uninstall them. This should be done judiciously and only after ensuring their functionality is no longer needed or has been replaced.

Step 4: Update Your Server Environment (PHP and Database)

Ensure your server meets Drupal 10's minimum requirements:
PHP: Upgrade PHP to version 8.1 or higher. PHP 8.2 is recommended.
Database: Ensure your database (MySQL, PostgreSQL, SQLite) is also at a compatible version. Refer to Drupal 10's official system requirements for the exact versions.

Step 5: Update Composer Dependencies and Drupal Core

Once your custom code and contrib modules are ready, and your server environment is updated, it's time to update Composer dependencies and Drupal core.

Update Composer.json: Modify your composer.json file to require Drupal 10.

"drupal/core-recommended": "^10.0",
"drupal/core-project-message": "^10.0",
"drupal/core-composer-scaffold": "^10.0",
"drupal/core-dev": "^10.0"

Run Composer Update:
```
composer update
```
This command will fetch the Drupal 10 core and update all other dependencies.

Step 6: Run Database Updates

After Composer has updated your codebase, run the database updates.

Drush:
```
drush updb
```
Web Browser: Navigate to YOUR_SITE_URL/update.php in your browser and follow the on-screen instructions.

Step 7: Clear Caches

Always clear caches after any significant update.
```
drush cr
```

Step 8: Comprehensive Testing

This is where your detailed testing plan comes into play. Execute all your test cases:

Verify all pages load correctly.
Test all forms, user registrations, and authentication flows.
Check all content creation, editing, and publishing workflows.
Review all views, blocks, and layout components.
Test any integrations with third-party services.
Perform thorough security and performance checks.
Conduct UAT with stakeholders.

If you encounter issues, review your server logs, Drupal's log messages, and consult the Drupal.org issue queues for modules. This is where the expertise of a professional drupal development agency or a skilled hire drupal developer can be invaluable for troubleshooting and resolving complex problems.

Step 9: Deploy to Production

Once your migrated site has passed all testing in the staging environment, you can plan and execute the deployment to your production server. Remember to:

Schedule Downtime: Inform your users of any planned downtime.
Backup Production: Take a final, full backup of your live Drupal 9 site.
Mirror the Process: Follow the same migration steps (update D9, fix code, update dependencies, run composer update, drush updb, drush cr) on the production server.
Final Verification: After deployment, perform a quick smoke test on the live site to ensure everything is functioning correctly.

Leveraging the Power of a Drupal Development Agency

While the migration from Drupal 9 to Drupal 10 is designed to be smoother than previous major upgrades, it still requires a deep understanding of Drupal’s architecture, modern PHP, Composer, and best development practices. For many organizations, especially those with complex sites, limited in-house resources, or tight deadlines, partnering with a specialized drupal development agency is a strategic move.

A reputable drupal company brings several advantages to the table:

Expertise: They have a team of experienced hire drupal developer professionals who are intimately familiar with Drupal's internals, migration paths, and common challenges.
Efficiency: Their experience allows them to execute migrations more efficiently, minimizing downtime and potential issues.
Tools and Best Practices: They utilize industry-standard tools, automation scripts, and established best practices to ensure a robust and secure migration.
Comprehensive Services: Beyond migration, a drupal development agency can offer ongoing support, performance optimization, security enhancements, and new feature development for your Drupal 10 site.
Reduced Risk: By outsourcing the migration to experts, you significantly reduce the risk of errors, data loss, or extended downtime.

Whether you're looking for ongoing drupal development support or a one-time migration, selecting the right partner is key to unlocking Drupal 10's full potential.

Common Pitfalls and How to Avoid Them

Even with careful planning, migrations can present unexpected challenges. Here are some common pitfalls and how to navigate them:

Ignoring the Upgrade Status Module: This module is your best friend. Skipping its detailed analysis can lead to nasty surprises later on.
Not Using Drupal Rector: Manually updating deprecated code is time-consuming and prone to errors. Embrace automation where possible.
Insufficient Testing: A hurried or incomplete testing phase is a recipe for disaster. Dedicate ample time and resources to testing.
Directly Migrating Production: Never, ever attempt a major upgrade directly on your live production site. Always use a staging environment.
Neglecting Custom Code: Custom modules and themes are often the biggest sources of migration headaches. Give them the attention they deserve.
Outdated Server Environment: Failing to upgrade PHP and your database to Drupal 10's requirements will prevent the upgrade from succeeding.
Lack of Backups: This can’t be stressed enough. Always have a reliable backup strategy in place.
Going It Alone: If your site is complex or your in-house team lacks deep Drupal expertise, don't hesitate to engage a drupal company. The investment in professional help often pays for itself in avoided headaches and faster, smoother transitions.

The Future is Bright with Drupal 10

Migrating to Drupal 10 is more than just an update; it's an investment in the future of your digital platform. You're adopting a more performant, secure, and user-friendly CMS that is poised for continued innovation. With its modernized architecture and commitment to continuous improvement, Drupal 10 ensures your website remains competitive, scalable, and adaptable to the ever-changing demands of the digital world.

From leveraging the latest PHP features to enjoying a refreshed administrative experience, Drupal 10 empowers your team and delights your users. The robust open-source community, coupled with dedicated drupal development agencies and skilled hire drupal developer talent, ensures that support and innovation are always within reach.

Conclusion: Embrace the Power of Drupal 10

The journey from Drupal 9 to Drupal 10 is a manageable and highly beneficial one. By following a structured approach, leveraging the right tools, and understanding the key considerations, you can ensure a seamless transition to the latest version of this powerful CMS. The benefits – from enhanced performance and security to a superior user and developer experience – far outweigh the effort involved.

Don't let your digital presence fall behind. Embrace Drupal 10 and unlock a world of new possibilities for your website. If you're ready to make the leap and require expert assistance, consider partnering with a leading drupal company that specializes in drupal development and migrations.

Ready to elevate your digital platform with Drupal 10?

Contact Us Today for a Consultation! Let our expert drupal development agency guide you through a smooth and successful migration, ensuring your website is primed for future growth and success.