diff --git a/src/sql/workbench/contrib/notebook/browser/models/untitledNotebookInput.ts b/src/sql/workbench/contrib/notebook/browser/models/untitledNotebookInput.ts
index a518424e4b..8b7b522dd7 100644
--- a/src/sql/workbench/contrib/notebook/browser/models/untitledNotebookInput.ts
+++ b/src/sql/workbench/contrib/notebook/browser/models/untitledNotebookInput.ts
@@ -26,6 +26,8 @@ export class UntitledNotebookInput extends NotebookInput {
 		@IExtensionService extensionService: IExtensionService
 	) {
 		super(title, resource, textInput, true, textModelService, instantiationService, notebookService, extensionService);
+		// Set the mode explicitly so that the auto language detection doesn't run and mark the model as being JSON
+		this.textInput.resolve().then(() => this.setMode('notebook'));
 	}
 
 	public override get textInput(): UntitledTextEditorInput {
diff --git a/src/sql/workbench/contrib/notebook/test/browser/notebookInput.test.ts b/src/sql/workbench/contrib/notebook/test/browser/notebookInput.test.ts
index 5f5ad24ea6..7a6c2bd169 100644
--- a/src/sql/workbench/contrib/notebook/test/browser/notebookInput.test.ts
+++ b/src/sql/workbench/contrib/notebook/test/browser/notebookInput.test.ts
@@ -84,7 +84,7 @@ suite('Notebook Input', function (): void {
 		// Input title
 		assert.strictEqual(untitledNotebookInput.getTitle(), testTitle);
 
-		let noTitleInput = instantiationService.createInstance(UntitledNotebookInput, undefined, untitledUri, undefined);
+		let noTitleInput = instantiationService.createInstance(UntitledNotebookInput, undefined, untitledUri, untitledTextInput);
 		assert.strictEqual(noTitleInput.getTitle(), basenameOrAuthority(untitledUri));
 
 		// Text Input