Custom Tooltip Not Passing Single-Country Filter Context When Y Axis Uses Conditional Logic

Hello ansza,
Thank you for posting your query in the Microsoft Fabric Community Forum.

As per Microsoft’s official documentation, report page tooltips rely on the filter context passed from the source visual:

“A report visual can only reveal a page tooltip when tooltip page filters are compatible with the visual's design.” Extend visuals with report page tooltips - Power BI | Microsoft Learn

Microsoft documentation also notes that tooltips are filtered by the data point being hovered:

“When you hover over a visual that includes the selected field, the tooltip appears and filters by the data point where your mouse is hovering.” Create Report Tooltips in Power BI - Power BI | Microsoft Learn

To preserve the correct filter context for tooltip functionality:

• Keep the Y-axis measure as the base measure (e.g., [Headcount])
• Implement Top N logic using a ranking or flag measure
• Apply that flag as a visual-level filter (e.g., Is TopN Country = 1)

This ensures that the Country field is truly filtered in the visual context, allowing the tooltip to receive the correct filter context and display accurate results. For your reference: Customize tooltips in Power BI

Best regards,
Ganesh Singamshetty.