⚠️ Acumatica will deprecate the Classic UI feature with the 2026 R2 release.
Customers who upgrade to 2026 R2, as well as new customers implementing 2026 R2, will no longer have the capability to turn off Modern UI. Acumatica will continue to support Classic UI in versions prior to 2026 R2 in accordance with our standard support policies.
This is an important step forward in Acumatica's commitment to delivering a faster, more consistent, and more capable product experience. Modern UI is the foundation of our innovation — it enables us to ship higher-quality features more quickly, with a unified design that scales across devices and use cases. Maintaining two parallel UI codebases creates significant engineering overhead that, over time, slows down our ability to deliver the best possible product to our customers. By focusing fully on Modern UI, we can invest that effort where it matters most: building features and improvements that benefit everyone.
Please read the Frequently Asked Questions (FAQ) below for further clarification on what this change means for you and how to prepare.
Contents
Getting Started
How do I switch from Classic UI to Modern UI before upgrading to 2026 R2?
Modern UI can be enabled in two ways. To switch your entire site, navigate to System Management > System Preferences > Site Preferences and set the default interface to Modern — this applies the change for all users. Alternatively, individual screens can be switched on the fly via the Tools menu (gear icon) > Switch to Modern UI. Switching ahead of your 2026 R2 upgrade is strongly recommended to give your team time to familiarize themselves with Modern UI before the transition becomes mandatory.
Is there a migration guide or checklist to help prepare for the transition?
Acumatica provides extensive documentation to help customers and partners get started with Modern UI and convert existing customizations. The UI Developer Guide covers Modern UI development patterns and migration approaches and is the recommended starting point for anyone preparing for the transition.
If I'm on a version prior to 2026 R2, when do I need to upgrade?
There is no immediate requirement to upgrade before 2026 R2. Classic UI remains available in all supported versions prior to 2026 R2, though no further enhancements will be delivered for it. We recommend beginning your transition to Modern UI as early as possible to allow sufficient time for testing, customization validation, and user training before the upgrade becomes necessary.
Customizations & Data
Will my existing data be affected when switching to Modern UI?
No. Switching to Modern UI is an interface change only — all records, transactions, configurations, and history should remain intact. Note that if customized screens have not been properly migrated to Modern UI, you may experience display issues that affect how your data appears. See the question below for guidance on managing customizations.
Do I need to rewrite all customizations after switching to Modern UI?
Not necessarily. Most business logic customizations remain unaffected. However, UI-specific customizations may require review and validation. Testing in a staging environment prior to upgrade is strongly recommended. Refer to Updating Customization Projects for the Modern UI for detailed guidance.
Known Issues & Workarounds
What are the known issues in Modern UI?
The list of known issues in Modern UI can be verified on the Partner Portal. Known issues are version-specific. Customers and partners should verify whether an issue is already resolved in a newer version and plan upgrades accordingly.
What if I discover a Modern UI bug where the only viable workaround is to revert to Classic UI? Won't that option disappear in 2026 R2?
Yes, reverting to Classic UI will no longer be an option starting with 2026 R2. However, with 2026 R1 we are introducing a special bug fixing mechanism exclusively for Modern UI bugs that reduces the downtime and cost of applying the fixes. We are also actively exploring whether this capability can be extended to 2025 R2, though we cannot commit to that outcome yet, it depends on technical feasibility work currently underway. Our goal is to ensure customers on the path to 2026 R2 feel supported, and the new patching capability is a meaningful part of that.
Some behaviors differ between Classic UI and Modern UI (for example, file upload or time entry format). Are these bugs?
No. Certain data input and interaction behaviors were intentionally redesigned in Modern UI. These differences are expected system behaviors and are not considered known issues.
How do I report a Modern UI issue that is blocking my move away from Classic UI?
If you encounter a Modern UI issue that is preventing your transition, please submit a support case through the standard Acumatica support process. When logging the case, clearly indicate that the issue is blocking your Classic UI deprecation transition so it can be appropriately prioritized. You can also check the Partner Portal to see if the issue is already known and whether a fix is available in a newer version.
Version & Support
Can Classic UI be enabled as an exception in 2026 R2 or later?
No. Classic UI cannot be enabled in 2026 R2 or later under any circumstances.
Does this affect customers on long-term or extended support versions?
Yes. Regardless of your support tier, Classic UI will not be available in 2026 R2 or later. Acumatica's standard support policies remain unchanged — supported versions prior to 2026 R2 will continue to be supported as normal, and Classic UI will remain available in those versions. However, once you upgrade to 2026 R2, Classic UI will no longer be available regardless of your support agreement.
Partners & Implementations
How does Classic UI deprecation affect new implementations being set up today?
New implementations should be set up using Modern UI from the start. Since Classic UI will not be available in 2026 R2 or later, beginning an implementation on Classic UI today would require an additional migration effort before or at the time of upgrade. Partners and customers starting new implementations are strongly encouraged to adopt Modern UI now to avoid rework and ensure a smoother upgrade path.
What guidance should partners give customers who are mid-implementation?
Partners working with customers who are currently mid-implementation on Classic UI should begin transitioning those projects to Modern UI as soon as possible. We recommend auditing any customized screens for Modern UI compatibility, updating customization projects using the guidance in the UI Developer Guide, and planning go-live on Modern UI ahead of the customer's eventual upgrade to 2026 R2.
What shall I do if my ISV solution is not compatible with Modern UI?
If your ISV solution is not compatible with Modern UI, you should contact the ISV to confirm their roadmap and availability of a Modern UI-compatible version. Starting from 2026 R2, Classic UI will no longer be available. If the ISV solution does not support Modern UI, upgrading to 2026 R2 or later may not be possible until compatibility is confirmed.
Resources & Help
Where can I get help if my team is struggling with the Modern UI transition?
If your team needs assistance with the Modern UI transition, the following resources are available: the UI Developer Guide for technical and customization guidance, the Partner Portal for known issues, and the standard Acumatica support process for case-specific assistance. Your Acumatica partner is also a key resource and should be your first point of contact for implementation and migration support.
Can I use the Modern Customer Portal in production?
No. For 2025 R2, the Modern Customer Portal is not supported in production environments. Production availability is planned for 2026 R1. For more information, see the Modern Customer Portal FAQ and Managed Availability Sign-Up.