diff --git a/Web/app.py b/Web/app.py
index 47d0ac6..9fcf2ed 100755
--- a/Web/app.py
+++ b/Web/app.py
@@ -76,6 +76,7 @@ from data_protection import (
 BASE_DIR = os.path.dirname(os.path.abspath(__file__))
 import settings as cfg
 from settings import MongoClient
+from tenant import get_tenant_context
 
 
 app = Flask(__name__, static_folder='static')  # Correctly set static folder
@@ -1092,6 +1093,15 @@ def inject_version():
                 client.close()
 
     current_module = _get_current_module(request.path)
+    current_tenant_db = MONGODB_DB
+    current_tenant_id = None
+    try:
+        ctx = get_tenant_context()
+        if ctx:
+            current_tenant_db = ctx.db_name or current_tenant_db
+            current_tenant_id = ctx.tenant_id
+    except Exception:
+        current_tenant_db = MONGODB_DB
 
     return {
         'APP_VERSION': APP_VERSION,
@@ -1104,6 +1114,8 @@ def inject_version():
         'is_admin': is_admin,
         'unread_notification_count': unread_notification_count,
         'current_permissions': current_permissions,
+        'current_tenant_db': current_tenant_db,
+        'current_tenant_id': current_tenant_id,
         'permission_action_options': PERMISSION_ACTION_OPTIONS,
         'permission_page_options': PERMISSION_PAGE_OPTIONS,
         'permission_presets': us.get_permission_preset_definitions(),
diff --git a/Web/templates/base.html b/Web/templates/base.html
index e07746d..75439bf 100755
--- a/Web/templates/base.html
+++ b/Web/templates/base.html
@@ -191,6 +191,17 @@
             white-space: nowrap;
             flex-shrink: 0;
         }
+
+        .navbar-text.tenant-badge {
+            font-size: 0.82rem;
+            color: rgba(255,255,255,0.9);
+            background: rgba(255,255,255,0.12);
+            border: 1px solid rgba(255,255,255,0.18);
+            padding: 0.25rem 0.55rem;
+            border-radius: 999px;
+            white-space: nowrap;
+            margin-right: 0.75rem;
+        }
         
         .navbar-brand::before {
             content: attr(data-icon);
@@ -1113,7 +1124,10 @@
                                 <button class="function-search-btn" type="submit">Los</button>
                             </form>
                         </div>
-                        <span class="navbar-text text-light me-3">{{ session['username'] }}</span>
+                        {% if current_tenant_db %}
+                        <span class="navbar-text tenant-badge" title="Aktive Tenant-Datenbank">{{ current_tenant_db }}</span>
+                    {% endif %}
+                    <span class="navbar-text text-light me-3">{{ session['username'] }}</span>
                         <div class="dropdown me-2 user-menu-wrap">
                             <button class="btn btn-secondary dropdown-toggle user-menu-btn" type="button" id="invUserMenuDropdown" data-bs-toggle="dropdown" aria-expanded="false" data-notification-button="true">
                                 👤