Extended Security Maintenance for Qt 5.15 begins May 2025

Standard support for Qt 5.15 will end after 26th of May 2025, as communicated earlier. After the support period, the release will be in EoS (End of Support) state and will only be supported through additional services, including Extended Security Maintenance for Qt 5.15, Extended Support, and Professional Services. Customers distributing applications and embedded devices using Qt 5.15 software should evaluate how to access technical support and maintenance patches which may include security fixes. Standard commercials terms still apply after End of Support.

Upgrade to Qt 6 now

We recommend upgrading to Qt 6 for any new software development projects. Qt 6.8 LTS, released in October 2024, will be supported and maintained up to October 2029 following recent changes to Qt LTS support period. Qt 6's tools & APIs empower designers and developers to create more through:

• Next-Generation User Experience - Build consistently branded 2D & 3D applications with a custom or native look & feel – using designer and developer-friendly tools, a leaner, yet more powerful QML language, and a flexible graphics architecture.
• Limitless Scalability - From microcontrollers (MCUs) to supercomputers, Qt 6 and our massive ecosystem provides everything you need to design, develop, and deploy software for your entire product line. Create applications that are beautiful in the front-end and powerful in the backend, with the same codebase for almost any hardware, leading OS, or on bare metal.

Or see the feature comparison between Qt 5.15 and 6.8 here.

Introducing Extended Security Maintenance for Qt 5.15

For some customers, it may not be feasible to upgrade to Qt 6. Customers who intend to extend their ability to maintain and secure their Qt 5.15-enabled devices and applications can now purchase a service subscription to Extended Security Maintenance for Qt 5.15 (ESM).

The subscription to Extended Security Maintenance for Qt 5.15 provides you access to Critical Vulnerability and Security (CVS) maintenance patches relating to most Qt libraries (third party libraries are not included, please refer to license agreement for the exact details) after the end-of-support (EoS) with the following conditions:

• The provided patches can be used by the organization across all applicable products.
• Each software developer will additionally need an active Developer License.
• The subscription does not include Technical Support, assistance applying the patches, or patches for 3rd party libraries or dependencies. Please contact us about Extended Support or Qt Professional Services if these are required.
• When security issues are confirmed, work will begin, and patches will be provided ASAP.
• ESM is only available for Qt 5.15. We may add other releases under ESM based on customer demand.

Find out more about Extended Security Maintenance for Qt 5.15 here.

Extended Support to help you with your burning issues with older versions of Qt

If you want to make sure you will not get stuck on technical issues, you may also need technical support for your project. You can purchase an Extended Support (ES) subscription, which will include standard support T&C for old Qt software already in EoS. ES comes with two limitations:

• Includes a max. 5 hours of work per ticket, additional hours available as service. Usually over 96% of all cases are closed in less than 5 hours.
• Specific to a Qt software version. ES is not limited to Qt 5.15, you can purchase ES for old Squish, Qt framework, Qt Creator or other currently unsupported software.
• ES is provided under Standard Support terms. Older software version reference development hosts and targets (HW + OS combinations) may be limited due to availability.

Find out more about Extended Support here.

Contact our Professional Services for any additional needs

If you have additional needs to what is offered under Extended Security Maintenance for Qt 5.15 and Extended Support, for example, support with your specific environment and hardware, we recommend setting it as a specific service for your needs. You can contact Qt Professional services to discuss a bespoke project to support with this.