diff --git a/src/libslic3r/GCode.cpp b/src/libslic3r/GCode.cpp
index 47bd6df40..13b21174a 100644
--- a/src/libslic3r/GCode.cpp
+++ b/src/libslic3r/GCode.cpp
@@ -3192,6 +3192,9 @@ std::string GCode::set_extruder(unsigned int extruder_id, double print_z)
         if (! start_filament_gcode.empty()) {
             // Process the start_filament_gcode for the filament.
             DynamicConfig config;
+            config.set_key_value("layer_num", new ConfigOptionInt(m_layer_index));
+            config.set_key_value("layer_z",   new ConfigOptionFloat(this->writer().get_position()(2) - m_config.z_offset.value));
+            config.set_key_value("max_layer_z", new ConfigOptionFloat(m_max_layer_z));
             config.set_key_value("filament_extruder_id", new ConfigOptionInt(int(extruder_id)));
             gcode += this->placeholder_parser_process("start_filament_gcode", start_filament_gcode, extruder_id, &config);
             check_add_eol(gcode);
@@ -3263,6 +3266,9 @@ std::string GCode::set_extruder(unsigned int extruder_id, double print_z)
     if (! start_filament_gcode.empty()) {
         // Process the start_filament_gcode for the new filament.
         DynamicConfig config;
+        config.set_key_value("layer_num", new ConfigOptionInt(m_layer_index));
+        config.set_key_value("layer_z",   new ConfigOptionFloat(this->writer().get_position()(2) - m_config.z_offset.value));
+        config.set_key_value("max_layer_z", new ConfigOptionFloat(m_max_layer_z));
         config.set_key_value("filament_extruder_id", new ConfigOptionInt(int(extruder_id)));
         gcode += this->placeholder_parser_process("start_filament_gcode", start_filament_gcode, extruder_id, &config);
         check_add_eol(gcode);