diff --git a/osf/models/user.py b/osf/models/user.py
index 560c7ea1324..72ca2b8f3f8 100644
--- a/osf/models/user.py
+++ b/osf/models/user.py
@@ -728,6 +728,11 @@ def merge_user(self, user):
         if self == user:
             raise ValueError('Cannot merge a user into itself')
 
+        # Capture content to SHARE reindex BEFORE merge transfers contributors
+        # After merge, user.contributed and user.preprints will be empty
+        nodes_to_reindex = list(user.contributed)
+        preprints_to_reindex = list(user.preprints.all())
+
         # Move over the other user's attributes
         # TODO: confirm
         for system_tag in user.system_tags.all():
@@ -859,13 +864,13 @@ def merge_user(self, user):
 
         from api.share.utils import update_share
 
-        for node in user.contributed:
+        for node in nodes_to_reindex:
             try:
                 update_share(node)
             except Exception as e:
                 logger.exception(f'Failed to SHARE reindex node {node._id} during user merge: {e}')
 
-        for preprint in user.preprints.all():
+        for preprint in preprints_to_reindex:
             try:
                 update_share(preprint)
             except Exception as e:
diff --git a/osf_tests/test_user.py b/osf_tests/test_user.py
index 14ea4969eaa..a2fc5b0e92a 100644
--- a/osf_tests/test_user.py
+++ b/osf_tests/test_user.py
@@ -442,6 +442,41 @@ def test_merge_drafts(self, user):
         assert not draft_five.has_permission(user2, permissions.READ)
         assert not draft_five.is_contributor(user2)
 
+    @mock.patch('api.share.utils.update_share')
+    def test_merge_user_triggers_share_reindex(self, mock_update_share):
+        from osf.models import Preprint
+
+        user = AuthUserFactory()
+        user2 = AuthUserFactory()
+
+        node_one = ProjectFactory(creator=user2, title='node_one')
+        node_two = ProjectFactory(title='node_two')
+        node_two.add_contributor(user2)
+
+        preprint_one = PreprintFactory(creator=user2, title='preprint_one')
+        preprint_two = PreprintFactory(title='preprint_two')
+        preprint_two.add_contributor(user2)
+
+        user.merge_user(user2)
+
+        # Verify update_share was called for both nodes
+        nodes_reindexed = [
+            call[0][0] for call in mock_update_share.call_args_list
+            if isinstance(call[0][0], AbstractNode)
+        ]
+        assert len(nodes_reindexed) == 2
+        assert node_one in nodes_reindexed
+        assert node_two in nodes_reindexed
+
+        # Verify update_share was called for both preprints
+        preprints_reindexed = [
+            call[0][0] for call in mock_update_share.call_args_list
+            if isinstance(call[0][0], Preprint)
+        ]
+        assert len(preprints_reindexed) == 2
+        assert preprint_one in preprints_reindexed
+        assert preprint_two in preprints_reindexed
+
     def test_cant_create_user_without_username(self):
         u = OSFUser()  # No username given
         with pytest.raises(ValidationError):