diff --git a/app/assets/javascripts/blob/file_template_mediator.js b/app/assets/javascripts/blob/file_template_mediator.js
index 583e5faa506..37074301b51 100644
--- a/app/assets/javascripts/blob/file_template_mediator.js
+++ b/app/assets/javascripts/blob/file_template_mediator.js
@@ -235,7 +235,7 @@ export default class FileTemplateMediator {
   }
 
   setFilename(name) {
-    this.$filenameInput.val(name);
+    this.$filenameInput.val(name).trigger('change');
   }
 
   getSelected() {
diff --git a/changelogs/unreleased/issue-42689-new-file-template.yml b/changelogs/unreleased/issue-42689-new-file-template.yml
new file mode 100644
index 00000000000..d6b77b87605
--- /dev/null
+++ b/changelogs/unreleased/issue-42689-new-file-template.yml
@@ -0,0 +1,5 @@
+---
+title: Trigger change event on filename input when file template is applied
+merge_request: 16911
+author: Sebastian Klingler
+type: fixed