diff --git a/events/utils.py b/events/utils.py
index 12b2f5c..382b2fd 100644
--- a/events/utils.py
+++ b/events/utils.py
@@ -167,6 +167,12 @@ def apply_sourcemaps(event_data):
                     frame['function'] = token.name
                     # frame["colno"] = token.src_col + TO_DISPLAY  not actually used
 
+            elif frame.get("filename") in debug_id_for_filename:
+                # The event_data reports that a debug_id is available for this filename, but we don't have it; this
+                # could be because the sourcemap was not uploaded. We want to show the debug_id in the stacktrace as
+                # a hint to the user that they should upload the sourcemap.
+                frame["debug_id"] = str(debug_id_for_filename[frame["filename"]])
+
 
 def get_sourcemap_images(event_data):
     # NOTE: butchered copy/paste of apply_sourcemaps; refactoring for DRY is a TODO
diff --git a/issues/templates/issues/stacktrace.html b/issues/templates/issues/stacktrace.html
index 65ded14..6036c72 100644
--- a/issues/templates/issues/stacktrace.html
+++ b/issues/templates/issues/stacktrace.html
@@ -146,7 +146,11 @@
 
                     {% if "context_line" not in frame or frame.context_line is None %}{% if not frame.vars %}{# nested ifs as a subsitute for brackets-in-templates #}
                     <div class="mt-6 mb-6 italic">
-                        No code context or variables available for this frame.
+                        {% if frame.debug_id %}{# only in the no-vars-either case to avoid excessive if-nesting (at the cost of completeness, but "will yes-vars, broken debug_id even be a case? For now we hope not) #}
+                            No sourcemaps found for Debug ID {{ frame.debug_id }}
+                        {% else %}
+                            No code context or variables available for this frame.
+                        {% endif %}
                     </div>
                     {% endif %}{% endif %}