diff --git a/CHANGELOG.md b/CHANGELOG.md
index 379d593c..70c2c151 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -44,6 +44,7 @@ RELEASING:
 ### Fixed
 - Delete annotations when plugin is uninstalled ([#346](https://github.com/GIScience/orstools-qgis-plugin/issues/346))
 - Reset hand cursor after deactivating line tool ([#342](https://github.com/GIScience/orstools-qgis-plugin/issues/342))
+- Set url slashes correctly with optimization requests in procs ([#347](https://github.com/GIScience/orstools-qgis-plugin/issues/347))
 
 ## [2.0.1] - 2025-06-01
 ### Added
diff --git a/ORStools/proc/directions_lines_proc.py b/ORStools/proc/directions_lines_proc.py
index 4d6436cb..f81b5467 100644
--- a/ORStools/proc/directions_lines_proc.py
+++ b/ORStools/proc/directions_lines_proc.py
@@ -190,7 +190,7 @@ def processAlgorithm(
                     endpoint = self.get_endpoint_names_from_provider(parameters[self.IN_PROVIDER])[
                         "optimization"
                     ]
-                    response = ors_client.request(f"{endpoint}/", {}, post_json=params)
+                    response = ors_client.request(f"/{endpoint}/", {}, post_json=params)
 
                     sink.addFeature(
                         directions_core.get_output_features_optimization(
diff --git a/ORStools/proc/directions_points_layer_proc.py b/ORStools/proc/directions_points_layer_proc.py
index 41c8d5cf..0f3310eb 100644
--- a/ORStools/proc/directions_points_layer_proc.py
+++ b/ORStools/proc/directions_points_layer_proc.py
@@ -231,7 +231,7 @@ def sort(f):
                     endpoint = self.get_endpoint_names_from_provider(parameters[self.IN_PROVIDER])[
                         "optimization"
                     ]
-                    response = ors_client.request(f"{endpoint}/", {}, post_json=params)
+                    response = ors_client.request(f"/{endpoint}/", {}, post_json=params)
 
                     sink.addFeature(
                         directions_core.get_output_features_optimization(
diff --git a/tests/test_proc.py b/tests/test_proc.py
index c13fc807..0cbd3c92 100644
--- a/tests/test_proc.py
+++ b/tests/test_proc.py
@@ -81,6 +81,32 @@ def test_directions_lines(self):
         feat_length = next(processed_layer.getFeatures()).geometry().length()
         self.assertTrue(feat_length > 0)
 
+    def test_directions_lines_layer_optimize(self):
+        parameters = {
+            "INPUT_AVOID_BORDERS": None,
+            "INPUT_AVOID_COUNTRIES": "",
+            "INPUT_AVOID_FEATURES": [],
+            "INPUT_AVOID_POLYGONS": None,
+            "INPUT_LAYER_FIELD": None,
+            "INPUT_LINE_LAYER": self.line_layer,
+            "INPUT_OPTIMIZE": 1,
+            "INPUT_PREFERENCE": 0,
+            "INPUT_PROFILE": 0,
+            "INPUT_PROVIDER": 0,
+            "INPUT_METRIC": 0,
+            "LOCATION_TYPE": 0,
+            "OUTPUT": "TEMPORARY_OUTPUT",
+        }
+
+        directions = ORSDirectionsLinesAlgo().create()
+        dest_id = directions.processAlgorithm(parameters, self.context, self.feedback)
+        processed_layer = QgsProcessingUtils.mapLayerFromString(dest_id["OUTPUT"], self.context)
+
+        self.assertEqual(type(processed_layer), QgsVectorLayer)
+
+        feat_length = next(processed_layer.getFeatures()).geometry().length()
+        self.assertTrue(feat_length > 0)
+
     def test_directions_points_layer(self):
         parameters = {
             "INPUT_AVOID_BORDERS": None,
@@ -108,6 +134,33 @@ def test_directions_points_layer(self):
 
         return processed_layer
 
+    def test_directions_points_layer_optimization(self):
+        parameters = {
+            "INPUT_AVOID_BORDERS": None,
+            "INPUT_AVOID_COUNTRIES": "",
+            "INPUT_AVOID_FEATURES": [],
+            "INPUT_AVOID_POLYGONS": None,
+            "INPUT_LAYER_FIELD": None,
+            "INPUT_OPTIMIZE": 1,
+            "INPUT_POINT_LAYER": self.point_layer_1,
+            "INPUT_PREFERENCE": 0,
+            "INPUT_PROFILE": 0,
+            "INPUT_PROVIDER": 0,
+            "INPUT_SORTBY": None,
+            "OUTPUT": "TEMPORARY_OUTPUT",
+        }
+
+        directions = ORSDirectionsPointsLayerAlgo().create()
+        dest_id = directions.processAlgorithm(parameters, self.context, self.feedback)
+        processed_layer = QgsProcessingUtils.mapLayerFromString(dest_id["OUTPUT"], self.context)
+
+        self.assertEqual(type(processed_layer), QgsVectorLayer)
+
+        feat_length = next(processed_layer.getFeatures()).geometry().length()
+        self.assertTrue(feat_length > 0)
+
+        return processed_layer
+
     def test_directions_points_layers(self):
         parameters = {
             "INPUT_AVOID_BORDERS": None,