Tag: Data Modeling

How to turn off Auto date/time in Power BI and why you might want to

Power BI includes a feature called Auto date/time that automatically creates hidden date tables for date columns in your model. While this can be helpful for quick analyses, it can also introduce performance issues and modeling complexity in more advanced or production-grade reports.

What Is Auto Date/Time?

When Auto date/time is enabled, Power BI automatically generates a hidden date table for every column of type Date or Date/Time. These tables allow you to use built-in time intelligence features (like Year, Quarter, and Month) without explicitly creating a calendar table.

Why Turn Off Auto Date/Time?

Disabling Auto date/time is often considered a best practice for the following reasons:

  • Better Performance
    Each date column gets its own hidden date table, which increases model size and can slow down report performance.
  • Cleaner Data Models
    Hidden tables can clutter the model and make debugging DAX calculations more difficult.
  • Consistent Time Intelligence
    Using a single, well-designed Date (Calendar) table ensures consistent logic across all measures and visuals.
  • More Control
    Custom calendar tables allow you to define fiscal years, custom week logic, holidays, and other business-specific requirements.

How to Turn Off Auto Date/Time in Power BI

You can disable Auto date/time in both Power BI Desktop and at the report level:

  1. In Power BI Desktop, go to FileOptions and settingsOptions.
  2. Under Global, select Data Load.
  3. Uncheck Auto date/time for new files.
  1. (Optional but recommended) Under Current File, select Data Load and uncheck Auto date/time to disable it for the current report.
  1. Click OK and refresh your model if necessary.

When Should You Leave It On?

Auto date/time can still be useful for:

  • Quick prototypes or ad-hoc analysis
  • Simple models with only one or two date fields
  • Users new to Power BI who are not yet working with custom DAX time intelligence

Final Thoughts

For enterprise, reusable, or performance-sensitive Power BI models, turning off Auto date/time and using a dedicated Date table is usually the better approach. It leads to cleaner models, more reliable calculations, and greater long-term flexibility as your reports grow in complexity.

Thanks for reading!