diff --git a/src/Mod/FreeCADExchange/AutoRouting.py b/src/Mod/FreeCADExchange/AutoRouting.py
index 46622ec..08ec063 100644
--- a/src/Mod/FreeCADExchange/AutoRouting.py
+++ b/src/Mod/FreeCADExchange/AutoRouting.py
@@ -1337,6 +1337,10 @@ def _route_segment_key(segment):
 
 def _route_segment_keys(result):
     route_track = result.get("route_track", {}) if isinstance(result, dict) else {}
+    return _route_track_segment_keys(route_track)
+
+
+def _route_track_segment_keys(route_track):
     segments = route_track.get("segments", []) if isinstance(route_track, dict) else []
     keys = []
     for segment in segments or []:
@@ -1346,6 +1350,35 @@ def _route_segment_keys(result):
     return keys
 
 
+def _incoming_wire_uuids(wires):
+    wire_uuids = set()
+    for item in wires or []:
+        if not isinstance(item, dict):
+            continue
+        wire_uuid = _wire_item_value(item, "wire_id", "wire_uuid", "id")
+        if wire_uuid:
+            wire_uuids.add(wire_uuid)
+    return wire_uuids
+
+
+def _existing_routed_segment_usage(doc, excluded_wire_uuids=None):
+    excluded_wire_uuids = set(excluded_wire_uuids or [])
+    usage = {}
+    for wire in list(WiringObjects.iter_routed_wire_objects(doc)):
+        if (getattr(wire, "RouteType", "") or "").strip() != "RoutedConnection":
+            continue
+        wire_uuid = (getattr(wire, "QetWireUuid", "") or "").strip()
+        if wire_uuid and wire_uuid in excluded_wire_uuids:
+            continue
+        try:
+            route_track = json.loads((getattr(wire, "QetRouteTrackJson", "") or "").strip() or "{}")
+        except Exception:
+            route_track = {}
+        for segment_key in _route_track_segment_keys(route_track):
+            usage[segment_key] = usage.get(segment_key, 0) + 1
+    return usage
+
+
 def bind_wire_task_terminals_from_payload(doc, payload):
     """Bind local template terminals to QET terminal UUIDs without creating wires."""
     if doc is None:
@@ -1427,7 +1460,10 @@ def route_eplan_connections_from_payload(doc, payload, options=None, prepared_la
     missing_endpoint_uuids = set()
     lane_indexes_by_pair = {}
     lane_indexes_by_segment = {}
-    segment_usage_costs = {}
+    segment_usage_costs = _existing_routed_segment_usage(
+        doc,
+        excluded_wire_uuids=_incoming_wire_uuids(wires),
+    )
 
     def add_status(status):
         key = str(status or "").strip() or "Unknown"
diff --git a/tests/python/freecad_exchange_auto_routing_test.py b/tests/python/freecad_exchange_auto_routing_test.py
index 3787c85..bb3f2d4 100644
--- a/tests/python/freecad_exchange_auto_routing_test.py
+++ b/tests/python/freecad_exchange_auto_routing_test.py
@@ -2035,6 +2035,68 @@ class AutoRoutingTest(unittest.TestCase):
         self.assertIn("Alternate Duct", second_labels)
         self.assertNotIn("Direct Duct", second_labels)
 
+    def test_route_eplan_connections_prefers_unused_segments_occupied_by_existing_wires(self):
+        _install_fake_freecad()
+        terminal_objects, _wiring_objects, routing_network, auto_routing = _reload_modules()
+        app = sys.modules["FreeCAD"]
+        doc = FakeDocument()
+        terminal_objects.ensure_root_group(doc, "project-1")
+        start = _terminal(doc, terminal_objects, "TerminalStart", "terminal-start", app.Vector(0, 0, 0))
+        end = _terminal(doc, terminal_objects, "TerminalEnd", "terminal-end", app.Vector(100, 0, 0))
+        routing_network.create_route_carrier(
+            doc,
+            [app.Vector(0, 0, 20), app.Vector(100, 0, 20)],
+            label="Direct Duct",
+            project_uuid="project-1",
+            kind="WireDuct",
+        )
+        routing_network.create_route_carrier(
+            doc,
+            [app.Vector(0, 0, 20), app.Vector(0, 40, 20)],
+            label="Left Bridge",
+            project_uuid="project-1",
+            kind="WireDuct",
+        )
+        routing_network.create_route_carrier(
+            doc,
+            [app.Vector(0, 40, 20), app.Vector(100, 40, 20)],
+            label="Alternate Duct",
+            project_uuid="project-1",
+            kind="WireDuct",
+        )
+        routing_network.create_route_carrier(
+            doc,
+            [app.Vector(100, 40, 20), app.Vector(100, 0, 20)],
+            label="Right Bridge",
+            project_uuid="project-1",
+            kind="WireDuct",
+        )
+        auto_routing.route_eplan_connection_between_terminals(
+            doc,
+            start,
+            end,
+            wire_uuid="existing-wire",
+        )
+        payload = {
+            "project_uuid": "project-1",
+            "wires": [
+                {
+                    "wire_id": "new-wire",
+                    "start_terminal_uuid": "terminal-start",
+                    "end_terminal_uuid": "terminal-end",
+                }
+            ],
+        }
+
+        report = auto_routing.route_eplan_connections_from_payload(doc, payload)
+
+        route_labels = [
+            segment["carrier"]["label"]
+            for segment in report["routes"][0]["route_track"]["segments"]
+        ]
+        self.assertIn("Alternate Duct", route_labels)
+        self.assertNotIn("Direct Duct", route_labels)
+
     def test_route_eplan_connections_report_includes_collision_samples(self):
         _install_fake_freecad()
         terminal_objects, _wiring_objects, routing_network, auto_routing = _reload_modules()