diff --git a/lib/gradelib.php b/lib/gradelib.php
index 38280108ecb..8b86b522d52 100644
--- a/lib/gradelib.php
+++ b/lib/gradelib.php
@@ -1625,9 +1625,9 @@ function grade_floats_equal($f1, $f2) {
  *
  * @param \stdClass $grade
  * @param \stdClass $user
- * @return int
+ * @return int|null
  */
-function grade_get_date_for_user_grade(\stdClass $grade, \stdClass $user): int {
+function grade_get_date_for_user_grade(\stdClass $grade, \stdClass $user): ?int {
     // The `datesubmitted` is the time that the grade was created.
     // The `dategraded` is the time that it was modified or overwritten.
     // If the grade was last modified by the user themselves use the date graded.
diff --git a/lib/tests/gradelib_test.php b/lib/tests/gradelib_test.php
index 8401916fd3c..a3e2b3d5667 100644
--- a/lib/tests/gradelib_test.php
+++ b/lib/tests/gradelib_test.php
@@ -160,7 +160,7 @@ class core_gradelib_testcase extends advanced_testcase {
      * @param stdClass $user
      * @param int $expected
      */
-    public function test_grade_get_date_for_user_grade(stdClass $grade, stdClass $user, int $expected): void {
+    public function test_grade_get_date_for_user_grade(stdClass $grade, stdClass $user, ?int $expected): void {
         $this->assertEquals($expected, grade_get_date_for_user_grade($grade, $user));
     }
 
@@ -191,12 +191,23 @@ class core_gradelib_testcase extends advanced_testcase {
             'datesubmitted' => 0,
         ];
 
+        $g3 = (object) [
+            'usermodified' => $u1->id,
+            'dategraded' => null,
+            'datesubmitted' => $d2,
+        ];
+
         return [
             'If the user is the last person to have modified the grade_item then show the date that it was graded' => [
                 $g1,
                 $u1,
                 $d1,
             ],
+            'If there is no grade and there is no feedback, then show graded date as null' => [
+                $g3,
+                $u1,
+                null,
+            ],
             'If the user is not the last person to have modified the grade_item, ' .
             'and there is no submission date, then show the date that it was submitted' => [
                 $g1,