diff --git a/backend/src/main/java/org/raddatz/familienarchiv/service/UserService.java b/backend/src/main/java/org/raddatz/familienarchiv/service/UserService.java
index 251acae4..eb136f71 100644
--- a/backend/src/main/java/org/raddatz/familienarchiv/service/UserService.java
+++ b/backend/src/main/java/org/raddatz/familienarchiv/service/UserService.java
@@ -183,27 +183,27 @@ public class UserService {
         }
 
         if (dto.getGroupIds() != null) {
-            Set<UUID> beforeIds = user.getGroups().stream().map(UserGroup::getId).collect(toSet());
-            Set<UserGroup> beforeGroups = new HashSet<>(user.getGroups());
-            Set<UserGroup> newGroups = new HashSet<>(groupRepository.findAllById(dto.getGroupIds()));
-            user.setGroups(newGroups);
-            Set<UUID> afterIds = newGroups.stream().map(UserGroup::getId).collect(toSet());
-            if (!beforeIds.equals(afterIds)) {
-                List<String> added = newGroups.stream()
-                        .filter(g -> !beforeIds.contains(g.getId()))
-                        .map(UserGroup::getName).toList();
-                List<String> removed = beforeGroups.stream()
-                        .filter(g -> !afterIds.contains(g.getId()))
-                        .map(UserGroup::getName).toList();
-                auditService.logAfterCommit(AuditKind.GROUP_MEMBERSHIP_CHANGED, actorId, null,
-                        Map.of("userId", id.toString(), "email", user.getEmail(),
-                                "addedGroups", added, "removedGroups", removed));
-            }
+            Set<UserGroup> before = new HashSet<>(user.getGroups());
+            Set<UserGroup> after = new HashSet<>(groupRepository.findAllById(dto.getGroupIds()));
+            user.setGroups(after);
+            groupChangePayload(before, after, id, user.getEmail())
+                    .ifPresent(payload -> auditService.logAfterCommit(AuditKind.GROUP_MEMBERSHIP_CHANGED, actorId, null, payload));
         }
 
         return userRepository.save(user);
     }
 
+    private Optional<Map<String, Object>> groupChangePayload(
+            Set<UserGroup> before, Set<UserGroup> after, UUID userId, String email) {
+        Set<UUID> beforeIds = before.stream().map(UserGroup::getId).collect(toSet());
+        Set<UUID> afterIds = after.stream().map(UserGroup::getId).collect(toSet());
+        if (beforeIds.equals(afterIds)) return Optional.empty();
+        List<String> added = after.stream().filter(g -> !beforeIds.contains(g.getId())).map(UserGroup::getName).toList();
+        List<String> removed = before.stream().filter(g -> !afterIds.contains(g.getId())).map(UserGroup::getName).toList();
+        return Optional.of(Map.of("userId", userId.toString(), "email", email,
+                "addedGroups", added, "removedGroups", removed));
+    }
+
     @Transactional
     public void changePassword(UUID userId, ChangePasswordDTO dto) {
         AppUser user = getById(userId);