diff --git a/InteractiveHtmlBom/core/config.py b/InteractiveHtmlBom/core/config.py
index 605a40bc..55371e0e 100644
--- a/InteractiveHtmlBom/core/config.py
+++ b/InteractiveHtmlBom/core/config.py
@@ -39,7 +39,7 @@ class Config:
         'dark_mode', 'show_pads', 'show_fabrication', 'show_silkscreen',
         'highlight_pin1', 'redraw_on_drag', 'board_rotation', 'checkboxes',
         'bom_view', 'layer_view', 'offset_back_rotation',
-        'kicad_text_formatting', 'mark_when_checked'
+        'kicad_text_formatting', 'mark_when_checked', 'custom_metadata'
     ]
     default_show_group_fields = ["Value", "Footprint"]
 
@@ -494,6 +494,10 @@ def add_options(cls, parser, version):
                             help='Name of the extra field that indicates '
                                  'do not populate status. Components with '
                                  'this field not empty will be excluded.')
+        parser.add_argument('--custom-metadata', default='',
+                            help='Custom metadata. Gets attached to '
+                                 'the BOM and can be accessed in '
+                                 'the user customization files.')
 
     def get_ini_defaults(self):
         # type: () -> dict | None
@@ -645,6 +649,7 @@ def set_from_args(self, args):
         self.board_variant_whitelist = self._split(args.variants_whitelist)
         self.board_variant_blacklist = self._split(args.variants_blacklist)
         self.dnp_field = args.dnp_field
+        self.custom_metadata = args.custom_metadata
 
     def get_html_config(self):
         import json
diff --git a/InteractiveHtmlBom/web/user-file-examples/user.js b/InteractiveHtmlBom/web/user-file-examples/user.js
index 4cffc3b1..4a3a3933 100644
--- a/InteractiveHtmlBom/web/user-file-examples/user.js
+++ b/InteractiveHtmlBom/web/user-file-examples/user.js
@@ -2,3 +2,23 @@
 // Event argument will always be {eventType, args} dict
 
 EventHandler.registerCallback(IBOM_EVENT_TYPES.ALL, (e) => console.log(e));
+
+// Example custom metadata (use with userheader.html)
+window.addEventListener("load", function () {
+  var meta = {};
+  try {
+    console.log(typeof config.custom_metadata);
+    console.log(JSON.stringify(config.custom_metadata));
+    meta = JSON.parse(config.custom_metadata || "{}");
+  } catch (e) {
+    console.error("custom_metadata is no valid JSON string:", e);
+  }
+
+  var element = document.getElementById("custom-metadata");
+  if (!element) return;
+
+  var text = "Drawing: " + (meta.drawing || "-") +
+             " | Customer: " + (meta.customer || "-");
+
+  element.textContent = text;
+});
diff --git a/InteractiveHtmlBom/web/user-file-examples/userheader.html b/InteractiveHtmlBom/web/user-file-examples/userheader.html
index bb597c57..e721c5ea 100644
--- a/InteractiveHtmlBom/web/user-file-examples/userheader.html
+++ b/InteractiveHtmlBom/web/user-file-examples/userheader.html
@@ -2,4 +2,7 @@
 <div style="width:100%; height: 50px;">
     Hello header
 </div>
+
+<!-- custom metadata (use with JSON string passed to --custom_metadata and user.js) -->
+<div id="custom-metadata" style="padding: 4px 8px; font-size: small;"></div>
 <div style="height: calc(100% - 100px)">