diff --git a/OpenRA.Mods.Common/Traits/World/PathFinderOverlay.cs b/OpenRA.Mods.Common/Traits/World/PathFinderOverlay.cs
index dfec513d72..86d24aed76 100644
--- a/OpenRA.Mods.Common/Traits/World/PathFinderOverlay.cs
+++ b/OpenRA.Mods.Common/Traits/World/PathFinderOverlay.cs
@@ -153,6 +153,12 @@ namespace OpenRA.Mods.Common.Traits
 			if (!Enabled || forActor == null)
 				yield break;
 
+			// Cull edges/costs to the visible viewport region to minimise rendering costs.
+			// But don't cull the target lines or abstract edges.
+			// These are long lines and so can easily clip into the region even if both ends are off-screen.
+			// There's not too many of them, so prefer to render them regardless.
+			var visibleRegion = wr.Viewport.AllVisibleCells;
+
 			foreach (var sourceCell in sourceCells)
 				yield return new TargetLineRenderable(new[]
 				{
@@ -160,16 +166,16 @@ namespace OpenRA.Mods.Common.Traits
 					self.World.Map.CenterOfSubCell(targetCell ?? sourceCell, SubCell.FullCell),
 				}, info.TargetLineColor, 8, 8);
 
-			foreach (var line in RenderEdges(self, abstractEdges1, 8, 6, info.AbstractColor1))
+			foreach (var line in RenderEdges(self, abstractEdges1, 8, 6, info.AbstractColor1, null))
 				yield return line;
 
-			foreach (var line in RenderEdges(self, abstractEdges2, 6, 4, info.AbstractColor2))
+			foreach (var line in RenderEdges(self, abstractEdges2, 6, 4, info.AbstractColor2, null))
 				yield return line;
 
-			foreach (var line in RenderEdges(self, localEdges1, 5, 3, info.LocalColor1))
+			foreach (var line in RenderEdges(self, localEdges1, 5, 3, info.LocalColor1, visibleRegion))
 				yield return line;
 
-			foreach (var line in RenderEdges(self, localEdges2, 4, 2, info.LocalColor2))
+			foreach (var line in RenderEdges(self, localEdges2, 4, 2, info.LocalColor2, visibleRegion))
 				yield return line;
 
 			if (!info.ShowCosts)
@@ -178,34 +184,41 @@ namespace OpenRA.Mods.Common.Traits
 			const int HorizontalOffset = 320;
 			const int VerticalOffset = 512;
 
-			foreach (var line in RenderCosts(self, abstractEdges1, new WVec(-HorizontalOffset, -VerticalOffset, 0), font, info.AbstractColor1))
+			foreach (var line in RenderCosts(self, abstractEdges1, new WVec(-HorizontalOffset, -VerticalOffset, 0), font, info.AbstractColor1, visibleRegion))
 				yield return line;
 
-			foreach (var line in RenderCosts(self, abstractEdges2, new WVec(-HorizontalOffset, VerticalOffset, 0), font, info.AbstractColor2))
+			foreach (var line in RenderCosts(self, abstractEdges2, new WVec(-HorizontalOffset, VerticalOffset, 0), font, info.AbstractColor2, visibleRegion))
 				yield return line;
 
-			foreach (var line in RenderCosts(self, localEdges1, new WVec(HorizontalOffset, -VerticalOffset, 0), font, info.LocalColor1))
+			foreach (var line in RenderCosts(self, localEdges1, new WVec(HorizontalOffset, -VerticalOffset, 0), font, info.LocalColor1, visibleRegion))
 				yield return line;
 
-			foreach (var line in RenderCosts(self, localEdges2, new WVec(HorizontalOffset, VerticalOffset, 0), font, info.LocalColor2))
+			foreach (var line in RenderCosts(self, localEdges2, new WVec(HorizontalOffset, VerticalOffset, 0), font, info.LocalColor2, visibleRegion))
 				yield return line;
 		}
 
-		static IEnumerable<IRenderable> RenderEdges(Actor self, Record edges, int nodeSize, int edgeSize, Color color)
+		static IEnumerable<IRenderable> RenderEdges(Actor self, Record edges, int nodeSize, int edgeSize, Color color, ProjectedCellRegion visibleRegion)
 		{
 			if (edges == null)
 				yield break;
 
 			var customColor = CustomLayerColor(color);
 			foreach (var (source, destination, _, _) in edges)
+			{
+				var srcUv = (PPos)source.ToMPos(self.World.Map);
+				var dstUv = (PPos)destination.ToMPos(self.World.Map);
+				if (visibleRegion != null && !visibleRegion.Contains(srcUv) && !visibleRegion.Contains(dstUv))
+					continue;
+
 				yield return new TargetLineRenderable(new[]
 				{
 					self.World.Map.CenterOfSubCell(source, SubCell.FullCell) + CustomLayerOffset(source),
 					self.World.Map.CenterOfSubCell(destination, SubCell.FullCell) + CustomLayerOffset(destination),
 				}, destination.Layer == 0 ? color : customColor, edgeSize, nodeSize);
+			}
 		}
 
-		static IEnumerable<IRenderable> RenderCosts(Actor self, Record edges, WVec textOffset, SpriteFont font, Color color)
+		static IEnumerable<IRenderable> RenderCosts(Actor self, Record edges, WVec textOffset, SpriteFont font, Color color, ProjectedCellRegion visibleRegion)
 		{
 			if (edges == null)
 				yield break;
@@ -213,6 +226,10 @@ namespace OpenRA.Mods.Common.Traits
 			var customColor = CustomLayerColor(color);
 			foreach (var (_, destination, costSoFar, estimatedRemainingCost) in edges)
 			{
+				var dstUv = (PPos)destination.ToMPos(self.World.Map);
+				if (!visibleRegion.Contains(dstUv))
+					continue;
+
 				var centerPos = self.World.Map.CenterOfSubCell(destination, SubCell.FullCell) +
 					CustomLayerOffset(destination) + textOffset;
 				yield return new TextAnnotationRenderable(font, centerPos, 0,