diff --git a/photo_tagger.py b/photo_tagger.py
index ff6c6e2..787e616 100644
--- a/photo_tagger.py
+++ b/photo_tagger.py
@@ -2848,8 +2848,93 @@ class PhotoTagger:
                 current_matched_index -= 1
                 update_display()
         
+        def has_unsaved_changes():
+            """Check if there are any unsaved changes in checkbox_states_per_person"""
+            return len(checkbox_states_per_person) > 0
+        
         def on_quit_auto_match():
             nonlocal window_destroyed
+            
+            # Check for unsaved changes before quitting
+            if has_unsaved_changes():
+                # Show warning dialog with custom width
+                from tkinter import messagebox
+                
+                # Create a custom dialog for better width control
+                dialog = tk.Toplevel(root)
+                dialog.title("Unsaved Changes")
+                dialog.geometry("500x250")
+                dialog.resizable(True, True)
+                dialog.transient(root)
+                dialog.grab_set()
+                
+                # Center the dialog
+                dialog.geometry("+%d+%d" % (root.winfo_rootx() + 50, root.winfo_rooty() + 50))
+                
+                # Main message
+                message_frame = ttk.Frame(dialog, padding="20")
+                message_frame.pack(fill=tk.BOTH, expand=True)
+                
+                # Warning icon and text
+                icon_label = ttk.Label(message_frame, text="⚠️", font=("Arial", 16))
+                icon_label.pack(anchor=tk.W)
+                
+                main_text = ttk.Label(message_frame, 
+                                    text="You have unsaved changes that will be lost if you quit.",
+                                    font=("Arial", 10))
+                main_text.pack(anchor=tk.W, pady=(5, 10))
+                
+                # Options
+                options_text = ttk.Label(message_frame,
+                                       text="• Yes: Save current changes and quit\n"
+                                            "• No: Quit without saving\n"
+                                            "• Cancel: Return to auto-match",
+                                       font=("Arial", 9))
+                options_text.pack(anchor=tk.W, pady=(0, 10))
+                
+                
+                # Buttons
+                button_frame = ttk.Frame(dialog)
+                button_frame.pack(fill=tk.X, padx=20, pady=(0, 20))
+                
+                result = None
+                
+                def on_yes():
+                    nonlocal result
+                    result = True
+                    dialog.destroy()
+                
+                def on_no():
+                    nonlocal result
+                    result = False
+                    dialog.destroy()
+                
+                def on_cancel():
+                    nonlocal result
+                    result = None
+                    dialog.destroy()
+                
+                yes_btn = ttk.Button(button_frame, text="Yes", command=on_yes)
+                no_btn = ttk.Button(button_frame, text="No", command=on_no)
+                cancel_btn = ttk.Button(button_frame, text="Cancel", command=on_cancel)
+                
+                yes_btn.pack(side=tk.LEFT, padx=(0, 5))
+                no_btn.pack(side=tk.LEFT, padx=5)
+                cancel_btn.pack(side=tk.RIGHT, padx=(5, 0))
+                
+                # Wait for dialog to close
+                dialog.wait_window()
+                
+                if result is None:  # Cancel - don't quit
+                    return
+                elif result:  # Yes - save changes first
+                    # Save current checkbox states before quitting
+                    save_current_checkbox_states()
+                    # Note: We don't actually save to database here, just preserve the states
+                    # The user would need to click Save button for each person to persist changes
+                    print("⚠️  Warning: Changes are preserved but not saved to database.")
+                    print("   Click 'Save Changes' button for each person to persist changes.")
+            
             if not window_destroyed:
                 window_destroyed = True
                 try: