Autodesk released Autodesk Civil 3D 2026 and the other related Autodesk Infrastructure products officially on April Fools Day 2025. Technically, the actual product downloads and/or deployment builds from the Autodesk Access app and the Autodesk Subscription site were not generally available until the second of April for most US customers.
In answer to the three most obvious questions:
No. There is no drawing format change in the raw AutoCAD dwg format.
Yes. There are significant raw performance reasons to Upgrade to the latest and greatest Civil 3D 2026 as soon as possible.
Yes. Based on our testing the recent Framework for Civil 3D 2025.2.1 product builds run great in Civil 3D 2026. No surprise there.
Most folks in Civil 3D Land will probably want to build and download a Deployment from the Autodesk Access app to get all the included goodies (the Drainage Analysis Preview, Grading Optimization (GO), etc. most easily into a functional Civil 3D 2026 install. The current available public downloadable build does not appear to successfully and easily construct effective installs.
Oh, bother. We can probably expect that to change real soon now. OK. Maybe I just missed something not so obvious?
Meanwhile, an Autodesk official Civil 3D 2026 video would be nice to see...
What’s New in Civil 3D 2026
Thanks John. We needed that.
Autodesk Civil 3D 2026
The new Civil 3D 2026 contains significant performance improvements based on the latest AutoCAD 2026 and Map 3D 2026 features and enhancements. Civil 3D program Start and File Open performance is significantly and visibly improved.
See the recent AutoCAD 2026 Arrives post.
These raw performance benefits and the new ability to tune the size of Surface DREFs are well worth a shout out for 2026. Hoorah.
There is nothing shabby about the new modal Model Viewer and Project Explorer (PE) open at the same time puttering over the details of a complex Corridor.
The PE Rocks.
See Autodesk's Ben Wardell's recent Project Explorer Back to Basics video playlist.
Enhancements
Read the Release Notes in the help.
Autodesk Drainage Analysis for Civil 3D Tech Preview
- Drainage Analysis for Civil 3D 2026 introduces a Technical Preview of an upcoming toolset designed to integrate the drainage design environment of Civil 3D with InfoDrainage analysis services hosted in the cloud.
- This extension enhances drainage design capabilities by providing new workflows for the design of ponds, underground storage devices, and open channels, as well as improved catchment delineation with expanded runoff method support.
New Surface Workflows
Support for partial Surfaces from dynamic boundaries from Data Reference (DREF) Surfaces.
- Create partial surfaces by defining a Boundaries to specify the display area of the surface. Boundaries are created by selecting existing polylines or by sketching new polylines.
- Add, modify, and delete the reference boundaries.
- Support for publishing partial surface data references.
- Support for exporting partial surface data references as LandXML.
- API for support for partial surface data reference workflows.
3D Model Viewer
- The new Model Viewer facilitates high-performance and isolated 3D review of selected objects within the Civil 3D environment. Open the viewer, select objects, and freely navigate those elements of your drawing.
- Review and edit complex objects such as Corridors and Subassemblies with the Model Viewer and Project Explorer in a new way that provides better insight without detracting from regular workflows.
New in Project Explorer
- In-depth support in Project Explorer for Rail Cant information and details.
Infrastructure Design Review in Autodesk Construction Cloud (ACC)
- The Civil Tools for Autodesk Construction Cloud (ACC) introduce alignment awareness and civil infrastructure-specific design review workflows for ACC. The tools enhance the design review process for infrastructure projects by providing the ability to interact with models in the context of project alignments.
- Within the Docs viewer, navigate along Alignment/Profile geometry, track their position with stationing information, create perpendicular cuts to the Alignments, and query data from a Corridor model.
- This new functionality allows BIM/CAD Managers, Project Managers, QA/QC personnel, and civil/design engineers, to collaborate on infrastructure projects within ACC.
New in Dynamo for Civil 3D
- This is another major upgrade to the capabilities of Dynamo for Civil 3D.
- Dynamo Core has been updated to version 3.4.1. The new Core provides us the improved TuneUp extension for monitoring graph performance as a built-in extension, package version compatibility information in Package Manager, PythonNet3 engine as a package, and more.
- See the New in Dynamo for Civil 3D 2026 page for the new added nodes and other details.
My Insights in Civil 3D
- Product usage Insights are displayed on the Start tab.
- My Insights is information that is shown to you based on your usage of Civil 3D. The content is designed to be informative and actionable. See what changes have been made to drawings and who made them.
Miscellaneous Enhancements
Coordinate System Updates
- Coordinate systems added for AutoCAD, Map and Civil 3D
Surface Performance Enhancements
- Rebuilding Corridor performance improvement for Corridors using a Surface as a target.
- Surface Analysis performance improvement.
- Performance improvement when cursor moves over a surface whose contours have large number of vertexes.
Customer Satisfaction Survey
- When we close Civil 3D, a customer satisfaction survey displays.
API Enhancements
- See the Civil 3D 2026 API Enhancements page for the specific Civil 3D API details.
Fixed Issues
- Read the Fixed Issues Release Notes for Civil 3D 2026.
Make Civil 3D Work Better
Get the Framework for Civil 3D