diff --git a/public/app/plugins/panel/barchart/utils.ts b/public/app/plugins/panel/barchart/utils.ts
index 9b25e678f1f..79d9629b11b 100644
--- a/public/app/plugins/panel/barchart/utils.ts
+++ b/public/app/plugins/panel/barchart/utils.ts
@@ -247,7 +247,7 @@ export const prepConfig = ({ series, totalSeries, color, orientation, options, t
       // use opacity from first numeric field
       let opacityField = frame.fields.find((f) => f.type === FieldType.number)!;
 
-      fillOpacity = (opacityField.config.custom.fillOpacity ?? 100) / 100;
+      fillOpacity = (opacityField?.config?.custom?.fillOpacity ?? 100) / 100;
 
       getColor = (seriesIdx: number, valueIdx: number) => {
         let field = frame.fields[seriesIdx];