diff --git a/EnvelopeGenerator.ReceiverUI/Pages/EnvelopeViewer.razor b/EnvelopeGenerator.ReceiverUI/Pages/EnvelopeViewer.razor
index 4e11446d..422f4fc1 100644
--- a/EnvelopeGenerator.ReceiverUI/Pages/EnvelopeViewer.razor
+++ b/EnvelopeGenerator.ReceiverUI/Pages/EnvelopeViewer.razor
@@ -12,6 +12,7 @@
 @inject IOptions<PdfViewerOptions> PdfViewerOptions
 @inject IJSRuntime JSRuntime
 @inject SignatureService SignatureService
+@inject EnvelopeGenerator.ReceiverUI.Services.AuthService AuthService
 @implements IAsyncDisposable
 
 <link href="_content/DevExpress.Blazor.Themes/blazing-berry.bs5.min.css" rel="stylesheet" />
@@ -35,6 +36,18 @@
                     <div class="envelope-key">ID: @EnvelopeKey</div>
                 </div>
             </div>
+            @if (!string.IsNullOrWhiteSpace(EnvelopeKey)) {
+                <button class="pdf-toolbar__btn" @onclick="LogoutAsync" disabled="@_isLoggingOut" title="Abmelden" style="margin-left: auto;">
+                    @if (_isLoggingOut) {
+                        <span class="spinner-border spinner-border-sm" role="status" aria-hidden="true" style="width: 14px; height: 14px;"></span>
+                    } else {
+                        <svg xmlns="http://www.w3.org/2000/svg" width="14" height="14" fill="currentColor" viewBox="0 0 16 16">
+                            <path fill-rule="evenodd" d="M10 12.5a.5.5 0 0 1-.5.5h-8a.5.5 0 0 1-.5-.5v-9a.5.5 0 0 1 .5-.5h8a.5.5 0 0 1 .5.5v2a.5.5 0 0 0 1 0v-2A1.5 1.5 0 0 0 9.5 2h-8A1.5 1.5 0 0 0 0 3.5v9A1.5 1.5 0 0 0 1.5 14h8a1.5 1.5 0 0 0 1.5-1.5v-2a.5.5 0 0 0-1 0v2z"/>
+                            <path fill-rule="evenodd" d="M15.854 8.354a.5.5 0 0 0 0-.708l-3-3a.5.5 0 0 0-.708.708L14.293 7.5H5.5a.5.5 0 0 0 0 1h8.793l-2.147 2.146a.5.5 0 0 0 .708.708l3-3z"/>
+                        </svg>
+                    }
+                </button>
+            }
         </div>
     </div>
 
@@ -377,6 +390,7 @@ int _currentPage = 1;
 int _totalPages = 0;
 int _currentZoom = 150;
 bool _showThumbnails = true;
+bool _isLoggingOut = false;
 DotNetObjectReference<EnvelopeViewer>? _dotNetRef;
 IReadOnlyList<SignatureDto> _signatures = [];
 
@@ -406,6 +420,14 @@ int _resizeStartWidth = 0;
 const int MinThumbnailWidth = 150;
 const int MaxThumbnailWidth = 400;
 
+    async Task LogoutAsync() {
+        if (string.IsNullOrWhiteSpace(EnvelopeKey) || _isLoggingOut) return;
+        _isLoggingOut = true;
+        await InvokeAsync(StateHasChanged);
+        await AuthService.LogoutEnvelopeReceiverAsync(EnvelopeKey);
+        Navigation.NavigateTo($"/login/{Uri.EscapeDataString(EnvelopeKey)}", forceLoad: true);
+    }
+
     protected override async Task OnInitializedAsync() {
         if (string.IsNullOrWhiteSpace(EnvelopeKey)) {
             _errorMessage = "Envelope-Schlüssel fehlt.";