diff --git a/.changeset/lovely-queens-own.md b/.changeset/lovely-queens-own.md
new file mode 100644
index 000000000..edc8dda2d
--- /dev/null
+++ b/.changeset/lovely-queens-own.md
@@ -0,0 +1,8 @@
+---
+'mermaid': patch
+---
+
+fix(block): overflowing blocks no longer affect later lines
+
+This may change the layout of block diagrams that have overflowing lines
+(i.e. block diagrams that use up more columns that the `columns` specifier).
diff --git a/cypress/integration/rendering/block.spec.js b/cypress/integration/rendering/block.spec.js
index 589a30fde..f01d59375 100644
--- a/cypress/integration/rendering/block.spec.js
+++ b/cypress/integration/rendering/block.spec.js
@@ -384,4 +384,17 @@ describe('Block diagram', () => {
       {}
     );
   });
+
+  it('BL30: block should overflow if too wide for columns', () => {
+    imgSnapshotTest(
+      `block-beta
+  columns 2
+  fit:2
+  overflow:3
+  short:1
+  also_overflow:2
+`,
+      {}
+    );
+  });
 });
diff --git a/packages/mermaid/src/diagrams/block/layout.ts b/packages/mermaid/src/diagrams/block/layout.ts
index a00e935ac..ea0de6312 100644
--- a/packages/mermaid/src/diagrams/block/layout.ts
+++ b/packages/mermaid/src/diagrams/block/layout.ts
@@ -270,7 +270,12 @@ function layoutBlocks(block: Block, db: BlockDB) {
       if (child.children) {
         layoutBlocks(child, db);
       }
-      columnPos += child?.widthInColumns ?? 1;
+      let columnsFilled = child?.widthInColumns ?? 1;
+      if (columns > 0) {
+        // Make sure overflowing lines do not affect later lines
+        columnsFilled = Math.min(columnsFilled, columns - (columnPos % columns));
+      }
+      columnPos += columnsFilled;
       log.debug('abc88 columnsPos', child, columnPos);
     }
   }