diff --git a/src/libslic3r/GCode/WipeTower.cpp b/src/libslic3r/GCode/WipeTower.cpp
index 5717aa0bb3..58af2da489 100644
--- a/src/libslic3r/GCode/WipeTower.cpp
+++ b/src/libslic3r/GCode/WipeTower.cpp
@@ -1183,7 +1183,9 @@ WipeTower::ToolChangeResult WipeTower::finish_layer()
     auto supported_rectangle = [this, &writer, spacing](const box_coordinates& wt_box, double feedrate, bool infill_cone) -> Polygon {
         const auto [R, support_scale] = get_wipe_tower_cone_base(m_wipe_tower_width, m_wipe_tower_height, m_wipe_tower_depth, m_wipe_tower_cone_angle);
 
-        double r = std::tan(Geometry::deg2rad(m_wipe_tower_cone_angle/2.f)) * (m_wipe_tower_height - m_layer_info->z);
+        double z = m_no_sparse_layers ? (m_current_height + m_layer_info->height) : m_layer_info->z; // the former should actually work in both cases, but let's stay on the safe side (the 2.6.0 is close)
+
+        double r = std::tan(Geometry::deg2rad(m_wipe_tower_cone_angle/2.f)) * (m_wipe_tower_height - z);
         Vec2f center = (wt_box.lu + wt_box.rd) / 2.;
         double w = wt_box.lu.y() - wt_box.ld.y();
         enum Type {
@@ -1313,9 +1315,11 @@ WipeTower::ToolChangeResult WipeTower::finish_layer()
 
     // Ask our writer about how much material was consumed.
     // Skip this in case the layer is sparse and config option to not print sparse layers is enabled.
-    if (! m_no_sparse_layers || toolchanges_on_layer || first_layer)
+    if (! m_no_sparse_layers || toolchanges_on_layer || first_layer) {
         if (m_current_tool < m_used_filament_length.size())
             m_used_filament_length[m_current_tool] += writer.get_and_reset_used_filament_length();
+        m_current_height += m_layer_info->height;
+    }
 
     return construct_tcr(writer, false, old_tool);
 }
@@ -1380,6 +1384,7 @@ void WipeTower::plan_tower()
 	for (auto& layer : m_plan)
 		layer.depth = 0.f;
     m_wipe_tower_height = m_plan.empty() ? 0.f : m_plan.back().z;
+    m_current_height = 0.f;
 	
     for (int layer_index = int(m_plan.size()) - 1; layer_index >= 0; --layer_index)
 	{
@@ -1471,6 +1476,7 @@ void WipeTower::generate(std::vector<std::vector<WipeTower::ToolChangeResult>> &
     }
 
     m_layer_info = m_plan.begin();
+    m_current_height = 0.f;
 
     // we don't know which extruder to start with - we'll set it according to the first toolchange
     for (const auto& layer : m_plan) {
diff --git a/src/libslic3r/GCode/WipeTower.hpp b/src/libslic3r/GCode/WipeTower.hpp
index 15b07f3d8c..561123d797 100644
--- a/src/libslic3r/GCode/WipeTower.hpp
+++ b/src/libslic3r/GCode/WipeTower.hpp
@@ -364,6 +364,10 @@ private:
 	std::vector<WipeTowerInfo> m_plan; 	// Stores information about all layers and toolchanges for the future wipe tower (filled by plan_toolchange(...))
 	std::vector<WipeTowerInfo>::iterator m_layer_info = m_plan.end();
 
+	// This sums height of all extruded layers, not counting the layers which
+	// will be later removed when the "no_sparse_layers" is used.
+	float m_current_height = 0.f;
+
     // Stores information about used filament length per extruder:
     std::vector<float> m_used_filament_length;