On Demand Webinar: Power BI User Defined Functions

What to Expect

Since September 2025, Power BI has introduced revolutionary new features – one of them is User Defined Functions (UDFs). With UDFs, you can encapsulate your own calculation logic into reusable functions and use them just like standard functions.

In just 30 minutes, we’ll show you live:

• How to create your own functions and use them in realistic scenarios,
• How to meaningfully integrate UDFs into your reports,
• How UDFs and Calculation Groups differ in direct comparison – and in which scenarios each is best applied.

Experience a compact live demo and gain practical insights you can immediately apply to your Power BI projects.

Why Use User Defined Functions?

• Reusable calculations – create once, use anywhere
• Better clarity & structure – neatly encapsulate business logic
• Flexibility – use your own calculations like standard functions
• Increased efficiency – save time on complex models
• Comparison to Calculation Groups – understand when each feature makes sense

Target Audience

Power BI users, controllers, data analysts

• Watch webinar recording

Our Speakers

Christian Fischer  Head of Sales, Partner

Salvatore Cagliari  Principal BI Consultant

Watch the recording here

User Defined Functions (UDFs) in Power BI – Smart, Reusable Business Logic

User Defined Functions (UDFs) allow you to create custom calculations once and reuse them anywhere in Power BI – in tables, charts, or reports. This saves time, reduces errors, and ensures consistent results.

Why UDFs are worth it:

• Create once, use anywhere: Define a calculation once and reuse it throughout your model.
• Easy to maintain: Changes to a function automatically apply everywhere it’s used.
• Work more reliably: UDFs help prevent errors and keep calculations accurate.
• Easy to access: UDFs are directly visible in your Power BI model and can be managed just like standard functions.
• Flexible application: Once created, functions can be used across all reports and dashboards – from simple evaluations to complex analyses.

Practical Example

A simple tax function could look like this:

As you can see: a few lines of code, big impact.

With UDFs, complex business logic can be elegantly encapsulated, making your Power BI reports faster, more structured, and easier to maintain.

Technical Advantages

UDFs extend Power BI with the ability to define custom calculations as parameterized, reusable functions. They bridge the gap between complex business logic and maintainable, consistent models.

• Reusable calculations: Define a calculation once and use it in measures, calculated columns, or visuals.
• Parameterized functions: Passing arguments enables flexible, dynamic calculations in real time.
• Error prevention & typing: Optional type hints in UDFs support input validation, minimize sources of error, and simplify model maintenance.
• Integration into the data model: UDFs are first-class objects in the Power BI model—visible in the Model Explorer, fully versionable, and manageable like standard functions.
• Reduced complexity & easier maintenance: Changes made to a central UDF are automatically applied everywhere it’s used – resulting in significantly less redundant DAX code.
• Optimized performance: Centralized calculation logic allows Power BI to plan evaluations more efficiently, especially for large models or complex scenarios.
• Comparison to Calculation Groups: UDFs encapsulate functional logic, while Calculation Groups efficiently represent temporal or dimensional variations – together, they form a robust reporting framework.

Practical Example:

With just a few lines of DAX, complex business logic can be built modularly and reused across all relevant reports.

Model integration: Once a UDF is defined, it can be directly incorporated into the Power BI model, and any changes automatically take effect in all reports using that function. This enables a centrally managed, reusable reporting framework without the need to repeatedly adjust individual measures or columns.

Conclusion

UDFs provide an elegant way to design complex calculations in a modular, efficient, and transparent manner—creating a consistent, scalable foundation for professional Power BI reports.

On Demand Webinar

Power BI User Defined Functions (UDFs)

• Watch webinar recording