diff --git a/src/compile/mark/encode/position-rect.ts b/src/compile/mark/encode/position-rect.ts
index 4223b149f4..9b2e131140 100644
--- a/src/compile/mark/encode/position-rect.ts
+++ b/src/compile/mark/encode/position-rect.ts
@@ -324,7 +324,7 @@ function rectBinPosition({
   const axis = (model.component.axes as any)[channel]?.[0];
   const axisTranslate = axis?.get('translate') ?? 0.5; // vega default is 0.5
 
-  const spacing = isXorY(channel) ? getMarkPropOrConfig('binSpacing', markDef, config) ?? 0 : 0;
+  const spacing = isXorY(channel) ? (getMarkPropOrConfig('binSpacing', markDef, config) ?? 0) : 0;
 
   const channel2 = getSecondaryRangeChannel(channel);
   const vgChannel = getVgPositionChannel(channel);