diff --git a/src/vs/editor/contrib/folding/browser/folding.ts b/src/vs/editor/contrib/folding/browser/folding.ts
index 8e203185c1b5b22d4cc8ef6408ff76f39db96ea2..02a63f6838eaf7358be2fb707727fb59c5f34f95 100644
--- a/src/vs/editor/contrib/folding/browser/folding.ts
+++ b/src/vs/editor/contrib/folding/browser/folding.ts
@@ -366,7 +366,7 @@ export class FoldingController implements editorCommon.IEditorContribution {
 				return false;
 			}
 			let decRange = dec.getDecorationRange(model);
-			return decRange && decRange.startLineNumber <= lineNumber && lineNumber < decRange.endLineNumber;
+			return decRange && decRange.startLineNumber <= lineNumber && lineNumber <= decRange.endLineNumber;
 		});
 	}