Matrix fixed column width keeps resetting

Hi terracottagull,

Hope you're doing well!

Here's a solution to try it step by step:

Disable Auto-size width: In the Matrix formatting pane, search for "auto" and turn off Auto-size column width. This is the first thing to verify, though even with "Auto-size column width" turned off, column widths can still reset under certain conditions.

REPT measure trick:

• Create a measure: ColWidth = REPT("X", N) sized to your longest value
• Turn on Auto-size width
• Add the measure to Values
• Turn off Auto-size width
• Remove the measure. This can make column sizes persist, including for new columns added after refresh. However, this trick targets value columns, not row-header columns specifically, results may vary for your use case.

Edit report metadata via PBIP format : Using the Power BI Projects (.pbip) format, you can directly set columnWidth properties in the layouts.json metadata file, which is more reliable than the UI for persistence. This is the most robust approach but requires working outside the UI.

Some useful ressources:

https://community.fabric.microsoft.com/t5/Desktop/Matrix-Table-resizing-columns-with-Autosize-column-turned-off/td-p/4755068

https://susheelaakulu.medium.com/fix-matrix-column-width-in-power-bi-5799921b7cf0

https://data-goblins.com/power-bi/set-column-widths

Hope this solution helps! Don't forget to accept as solution ✅ and give kudos 👍 in order to keep helping others.

Best regards,

Oussama (Data Consultant - E