diff --git a/src/road_cmd.cpp b/src/road_cmd.cpp
index a824fd21d8..5a1cf34eac 100644
--- a/src/road_cmd.cpp
+++ b/src/road_cmd.cpp
@@ -413,7 +413,7 @@ static CommandCost CheckRoadSlope(Slope tileh, RoadBits *pieces, RoadBits existi
 	if (_settings_game.construction.build_on_slopes && (_invalid_tileh_slopes_road[0][tileh] & (other | type_bits)) == ROAD_NONE) {
 
 		/* If we add leveling we've got to pay for it */
-		if ((other | existing) == ROAD_NONE) return CommandCost(EXPENSES_CONSTRUCTION, _price[PR_TERRAFORM]);
+		if ((other | existing) == ROAD_NONE) return CommandCost(EXPENSES_CONSTRUCTION, _price[PR_BUILD_FOUNDATION]);
 
 		return CommandCost();
 	}