Conditional formatting for matrix column headers based on closed month

Hi RAYAN123, 

Currently, Power BI does not support conditional formatting for matrix column headers. Conditional formatting can only be applied to values within the visual, not to row or column headers.

If your requirement is to dynamically color the month header itself, you can use the Deneb custom visual.

 

I have provided below Deneb custom visual example using Sample Data - Time Sample

1. Create a custom column MonthHeaderColor

MonthHeaderColor = 
IF(
    'Time Sample'[IsClosedMonth] = TRUE(),
    "#70AD47",   -- Green
    "#A6A6A6"    -- Grey
)

2. Add Month, MonthNo, IsClosedMonth and MonthHeaderColor to the Values in Deneb Visual.

3. Edit Visual and select Vega-Lite (empty).

4. Add below to the Specification section and Run.

{
  "$schema": "https://vega.github.io/schema/vega-lite/v5.json",
  "data": { "name": "dataset" },

  "transform": [
    {
      "calculate": "'Header'",
      "as": "HeaderRow"
    }
  ],

  "width": { "step": 70 },
  "height": 45,

  "layer": [
    {
      "mark": {
        "type": "rect",
        "stroke": "white",
        "strokeWidth": 1,
        "cornerRadius": 2
      },
      "encoding": {
        "x": {
          "field": "Month",
          "type": "ordinal",
          "sort": { "field": "MonthNo", "order": "ascending" },
          "axis": null
        },
        "y": {
          "field": "HeaderRow",
          "type": "nominal",
          "axis": null
        },
        "color": {
          "field": "MonthHeaderColor",
          "type": "nominal",
          "scale": null,
          "legend": null
        },
        "tooltip": [
          { "field": "Month", "type": "nominal", "title": "Month" },
          { "field": "IsClosedMonth", "type": "nominal", "title": "Closed?" }
        ]
      }
    },
    {
      "mark": {
        "type": "text",
        "align": "center",
        "baseline": "middle",
        "fontSize": 13,
        "fontWeight": "bold",
        "color": "white"
      },
      "encoding": {
        "x": {
          "field": "Month",
          "type": "ordinal",
          "sort": { "field": "MonthNo", "order": "ascending" }
        },
        "y": {
          "field": "HeaderRow",
          "type": "nominal"
        },
        "text": {
          "field": "Month",
          "type": "nominal"
        }
      }
    }
  ],

  "config": {
    "view": {
      "stroke": null
    }
  }
}

5. Result 

💡 Helpful? Give a Kudos 👍 — keep the community growing
✅ Solved your issue? Mark as Solution ✔️ — help others find it faster

Best regards,
Rupasree Achari | BI & Fabric Analytics Engineer