diff --git a/bec_widgets/widgets/plots/waveform/settings/curve_settings/curve_tree.py b/bec_widgets/widgets/plots/waveform/settings/curve_settings/curve_tree.py
index a992354b..ab7bb703 100644
--- a/bec_widgets/widgets/plots/waveform/settings/curve_settings/curve_tree.py
+++ b/bec_widgets/widgets/plots/waveform/settings/curve_settings/curve_tree.py
@@ -127,13 +127,13 @@ class CurveRow(QTreeWidgetItem):
         # Populate 'live' and all available history scan indices
         self.scan_index_combo.addItem("live")
         history = getattr(self.curve_tree.client, "history", None)
-        num_scans = len(history) if history is not None else 0
+        scan_number_list = history._scan_numbers  # len(history) if history is not None else 0
         # Restrict input to 'live' or valid scan numbers
-        validator = ScanIndexValidator(num_scans, self.scan_index_combo)
+        validator = ScanIndexValidator(len(scan_number_list), self.scan_index_combo)
         self.scan_index_combo.lineEdit().setValidator(validator)
-        for idx in range(num_scans):
+        for idx in scan_number_list:
             # Display scan numbers starting at 1
-            self.scan_index_combo.addItem(str(idx + 1))
+            self.scan_index_combo.addItem(str(idx))
         # Select current scan number if set, otherwise default to 'live'
         if getattr(self.config, "scan_number", None) is not None:
             self.scan_index_combo.setCurrentText(str(self.config.scan_number))
diff --git a/tests/unit_tests/test_curve_settings.py b/tests/unit_tests/test_curve_settings.py
index d7597d5f..13bb69c4 100644
--- a/tests/unit_tests/test_curve_settings.py
+++ b/tests/unit_tests/test_curve_settings.py
@@ -418,6 +418,7 @@ def test_export_data_history_curve(curve_tree_fixture, scan_history_factory):
     for m in msgs:
         wf.client.history._scan_data[m.scan_id] = m
         wf.client.history._scan_ids.append(m.scan_id)
+        wf.client.history._scan_numbers.append(m.scan_number)
     wf.client.queue.scan_storage.current_scan = None
 
     # Create a device row and select scan index "2"