Power BI Service now lets teams write DAX measures on Fabric models
Reviewed by Helen Jones
Training demos and June 2026 Power BI updates confirm that users can create and manage DAX measures, set relationships, and do modeling work in the Power BI Service when the dataset sits on a Microsoft Fabric Lakehouse. Copilot in web modeling (still preview) can draft measures, renames, and relationships from natural language. Those service-built datasets can be opened from Power BI Desktop through the OneLake data hub in Direct Lake mode. The path needs a Fabric trial or capacity and a Lakehouse. Live connection from Desktop does not expose the data view, and some advanced authoring such as certain DAX user-defined functions remains limited in the Service.
Until recently, serious semantic model work and DAX lived almost entirely in Desktop.pbix files. That meant one person held the file, measure changes waited on a republish, and browser-only colleagues could only consume what someone else had already built. Shared workspaces held reports, not the modeling conversation. Browser modeling on Fabric-backed datasets changes the handoff pattern more than it changes the hard problems. Two people can adjust the same measure in a workspace without emailing a Desktop file, and Direct Lake can keep performance closer to import while reading lake data. The numbers still only earn trust if the KPI definition, relationships, and refresh ownership are clear. Copilot can draft DAX quickly, but it does not prove the total matches Excel or the source system.
Analysis
Treat this as a collaboration test, not a reason to migrate every report into Fabric. If you already have Fabric capacity and a Lakehouse-backed model, pick one measure stakeholders argue about, write or edit it in the Service with a second person watching, then compare the result to your Excel or source check before you rely on it for the monthly pack.
Source note
Pulse published by Collab365 Spaces, reviewed by Helen Jones on . Cite as "Power BI Service now lets teams write DAX measures on Fabric models", Collab365 Spaces. 2 sources referenced.