diff --git a/packages/block-library/src/columns/style.scss b/packages/block-library/src/columns/style.scss
index 0ff22eb66bbbd0..67c6df277095dc 100644
--- a/packages/block-library/src/columns/style.scss
+++ b/packages/block-library/src/columns/style.scss
@@ -39,7 +39,7 @@
 	// the border block support allowing user defined borders.
 	&.is-style-divided .wp-block-column {
 		// Default divided border to use until user specifies something different.
-		border: 1px solid $gray-300;
+		border: 1px solid $gray-900;
 
 		// Disable top and left borders.
 		border-top: none !important;