diff --git a/src/buffer.cc b/src/buffer.cc
index d59977fe..2ee56106 100644
--- a/src/buffer.cc
+++ b/src/buffer.cc
@@ -138,7 +138,7 @@ bool BufferIterator::is_end() const
 
 Buffer::Buffer(const std::string& name, const BufferString& initial_content)
     : m_name(name), m_history(1), m_history_cursor(m_history.begin()),
-      m_content(initial_content)
+      m_content(initial_content), m_last_save_undo_group(m_history.begin())
 {
     BufferManager::instance().register_buffer(this);
 
@@ -350,4 +350,15 @@ void Buffer::delete_window(Window* window)
     m_windows.erase(window_it);
 }
 
+bool Buffer::is_modified() const
+{
+    return m_last_save_undo_group != m_history_cursor
+           or not m_current_undo_group.empty();
+}
+
+void Buffer::notify_saved()
+{
+    m_last_save_undo_group = m_history_cursor;
+}
+
 }
diff --git a/src/buffer.hh b/src/buffer.hh
index 565dfea5..b3ed56fc 100644
--- a/src/buffer.hh
+++ b/src/buffer.hh
@@ -106,6 +106,9 @@ public:
     Window* get_or_create_window();
     void delete_window(Window* window);
 
+    bool is_modified() const;
+    void notify_saved();
+
 private:
     BufferChar at(BufferPos position) const;
 
@@ -144,7 +147,7 @@ private:
 
     std::vector<UndoGroup>           m_history;
     std::vector<UndoGroup>::iterator m_history_cursor;
-    UndoGroup                              m_current_undo_group;
+    UndoGroup                        m_current_undo_group;
 
     void replay_modification(const Modification& modification);
     void revert_modification(const Modification& modification);
@@ -152,6 +155,8 @@ private:
     void append_modification(Modification&& modification);
 
     std::list<std::unique_ptr<Window>> m_windows;
+
+    std::vector<UndoGroup>::iterator m_last_save_undo_group;
 };
 
 }
diff --git a/src/main.cc b/src/main.cc
index 19ff9e0f..99965f7e 100644
--- a/src/main.cc
+++ b/src/main.cc
@@ -382,6 +382,7 @@ void write_buffer(const CommandParameters& params)
     std::string filename = params.empty() ? buffer.name() : params[0];
 
     write_buffer_to_file(buffer, filename);
+    buffer.notify_saved();
 }
 
 bool quit_requested = false;
diff --git a/src/window.cc b/src/window.cc
index f75c08b1..34baaee6 100644
--- a/src/window.cc
+++ b/src/window.cc
@@ -332,18 +332,26 @@ std::string Window::status_line() const
 {
     BufferCoord cursor = window_to_buffer(cursor_position());
     std::ostringstream oss;
-    oss << m_buffer.name() << " -- " << cursor.line << "," << cursor.column
+    oss << m_buffer.name();
+    if (m_buffer.is_modified())
+        oss << " [+]";
+    oss << " -- " << cursor.line << "," << cursor.column
         << " -- " << m_selections.size() << " sel -- ";
-    switch (m_select_mode)
+    if (m_current_inserter)
+        oss << "[Insert]";
+    else
     {
-    case SelectMode::Normal:
-        oss << "[Normal]";
-        break;
-    case SelectMode::Append:
-        oss << "[Append]";
-        break;
-    default:
-        assert(false);
+        switch (m_select_mode)
+        {
+        case SelectMode::Normal:
+            oss << "[Normal]";
+            break;
+        case SelectMode::Append:
+            oss << "[Append]";
+            break;
+        default:
+            assert(false);
+        }
     }
     return oss.str();
 }