diff --git a/intern/cycles/blender/blender_sync.cpp b/intern/cycles/blender/blender_sync.cpp
index 4b2fa61e01c..8180aa0c948 100644
--- a/intern/cycles/blender/blender_sync.cpp
+++ b/intern/cycles/blender/blender_sync.cpp
@@ -554,7 +554,7 @@ SessionParams BlenderSync::get_session_params(BL::RenderEngine b_engine,
 		params.tile_size = make_int2(tile_x, tile_y);
 	}
 
-	if(BlenderSession::headless == false) {
+	if((BlenderSession::headless == false) && background) {
 		params.tile_order = (TileOrder)RNA_enum_get(&cscene, "tile_order");
 	}
 	else {
diff --git a/intern/cycles/render/tile.cpp b/intern/cycles/render/tile.cpp
index 14fd89e1a39..37b9647f84a 100644
--- a/intern/cycles/render/tile.cpp
+++ b/intern/cycles/render/tile.cpp
@@ -155,7 +155,10 @@ int TileManager::gen_tiles(bool sliced)
 					cur_tiles++;
 
 					if(cur_tiles == tiles_per_device) {
-						tile_list->sort(TileComparator(tile_order, center));
+						/* Tiles are already generated in Bottom-to-Top order, so no sort is necessary in that case. */
+						if(tile_order != TILE_BOTTOM_TO_TOP) {
+							tile_list->sort(TileComparator(tile_order, center));
+						}
 						tile_list++;
 						cur_tiles = 0;
 						cur_device++;