March 6, 2026, QGIS 4.0 "Norrköping" was officially released. This is the first major version update in approximately eight years, since the release of QGIS 3.0 "Girona" on February 23, 2018.
Although QGIS 4.0 experienced several delays, good things come to those who wait, and the new version is finally here. Below is an introduction to the key points of the QGIS 4.0 release, as well as important considerations when migrating from 3.x to 4.x.
PS: As of the publication of this article, pre-compiled binary packages are not yet available on either the QGIS official website or GitHub. Users who wish to try it out and have the technical capability can attempt to compile it locally. The editor suggests waiting a few days for the official update on the website, as there's no need to go through the trouble.
Key Updates in QGIS 4.0
The biggest change in QGIS 4.0 is upgrading the UI framework from Qt5 to Qt6. For users, the interface and operational habits will see minimal changes. Efforts were also made to retain some deprecated APIs to ease the migration burden for plugin developers, with the official team providing a migration guide and the pyqgis4-checker compatibility tool.
However, the benefits of this migration are also clear:
- Performance Improvements
- Enhanced Security
- Support for New Libraries
- Improved Maintainability
Of course, there are also nearly a hundred functional updates, such as:
- Temporal raster layers
- Support for point cloud data type expressions in Processing
- Qt6 High DPI and multi-monitor support, offering better interface scaling and multi-screen experience
- Optimizations in map rendering and drawing performance
- Enhancements in expressions and form-related capabilities
- Improvements in layout and printing workflows
- Updates to data source and OGC standard support
- Support for plugin migration
- Security and dependency updates, modernization of underlying libraries.
...
Should You Upgrade?
Although QGIS 4.0 has been released and many are eager to upgrade immediately, the editor advises caution. It is foreseeable that QGIS 3.44 will continue to be provided as the LTR (Long Term Release) version for a considerable period. According to the official roadmap, the LTR version of QGIS 4.0 is expected around October 2026. Therefore, for scenarios requiring stable operation, such as business or research, the editor still recommends not upgrading in production environments and continuing to use the QGIS 3.44 LTR version. Only after independently testing the stability and compatibility of QGIS 4.0 should an upgrade be considered.
Apart from that, if it's only for testing purposes, or if QGIS is not a core tool in your daily work, the editor suggests upgrading. The focus of future plugins and the supporting ecosystem will shift towards QGIS 4.0. Starting early allows for earlier adaptation, especially considering the benefits mentioned above – QGIS 4.0 brings not just feature iterations, but also increased speed and security.
Impact on Existing Plugins
Thanks to the thoughtful design of QGIS 4.0, even with the major version jump from 3 to 4, most plugins should still function correctly. The development team strived to enable plugin developers to migrate with minimal changes while advancing the 4.x series. However, some plugins may encounter compatibility issues, for example:
1. Plugins still using old APIs from the QGIS 2.x era
QGIS 4.x currently maintains compatibility with the old QGIS 2.x APIs, so existing plugins won't fail immediately. However, the development team does not guarantee maintaining these old APIs throughout the entire lifecycle of 4.x; they may be dropped in future updates, so caution is advised.
2. Plugins that only support Qt5
The GUI framework "Qt" in QGIS 4.x only supports Qt6. Plugins developed specifically for Qt5 are highly unlikely to run in QGIS 4.x.
So how can you check the compatibility of the plugins you use? The official QGIS plugin repository provides a list of "QGIS 4 Ready Plugins" – plugins confirmed to be compatible with QGIS 4. If you're concerned about whether your daily-use plugins are compatible with QGIS 4, you can check this list.
Address: QGIS 4 Ready Plugins (Official QGIS Plugin Site)
Conclusion
QGIS 4.x has undergone significant internal improvements in performance, security, and more by migrating from Qt5 to Qt6. The interface changes are minimal, allowing users to maintain their existing workflows while using QGIS in a more stable environment. In the short term, QGIS 3.44 remains the LTR version, planned to be succeeded by QGIS 4.2 LTR around October 2026. Subsequently, the 4.x series will gradually become the mainstream.
Finally, the editor poses a question: ESRI, which has fully ceased support for ArcGIS Desktop, has gone "All in" on ArcGIS Pro. ArcGIS Pro vs QGIS – who do you think is the better choice?