diff --git a/addons/sale_stock/tests/test_sale_stock.py b/addons/sale_stock/tests/test_sale_stock.py
index 5b83158a843..ab76630efad 100644
--- a/addons/sale_stock/tests/test_sale_stock.py
+++ b/addons/sale_stock/tests/test_sale_stock.py
@@ -1313,3 +1313,40 @@ class TestSaleStock(TestSaleCommon, ValuationReconciliationTestCommon):
                 line.product_uom_qty = 8
 
         self.assertEqual(so.picking_ids.move_ids.product_uom_qty, 8)
+
+    def test_backorder_and_decrease_sol_qty(self):
+        """
+        2 steps delivery
+        SO with 10 x P
+        Process pickings of 6 x P with backorders
+        Update SO: 7 x P
+        Backorder should be updated: 1 x P
+        """
+        warehouse = self.company_data['default_warehouse']
+        warehouse.delivery_steps = 'pick_ship'
+        stock_location = warehouse.lot_stock_id
+        out_location = warehouse.wh_output_stock_loc_id
+        customer_location = self.env.ref('stock.stock_location_customers')
+
+        so = self._get_new_sale_order()
+        so.action_confirm()
+        pick01, ship01 = so.picking_ids
+
+        pick01.move_line_ids.qty_done = 6
+        pick01._action_done()
+        pick02 = pick01.backorder_ids
+
+        ship01.move_line_ids[0].qty_done = 6
+        ship01._action_done()
+        ship02 = ship01.backorder_ids
+
+        so.order_line.product_uom_qty = 7
+
+        self.assertRecordValues(so.picking_ids.move_ids.sorted('id'), [
+            {'location_id': out_location.id, 'location_dest_id': customer_location.id, 'product_uom_qty': 6.0, 'quantity_done': 6.0, 'state': 'done'},
+            {'location_id': stock_location.id, 'location_dest_id': out_location.id, 'product_uom_qty': 6.0, 'quantity_done': 6.0, 'state': 'done'},
+            {'location_id': stock_location.id, 'location_dest_id': out_location.id, 'product_uom_qty': 1.0, 'quantity_done': 0.0, 'state': 'assigned'},
+            {'location_id': out_location.id, 'location_dest_id': customer_location.id, 'product_uom_qty': 1.0, 'quantity_done': 0.0, 'state': 'waiting'},
+        ])
+        self.assertEqual(ship01.move_ids.move_orig_ids, (pick01 | pick02).move_ids)
+        self.assertEqual(ship02.move_ids.move_orig_ids, (pick01 | pick02).move_ids)
diff --git a/addons/stock/models/stock_move.py b/addons/stock/models/stock_move.py
index 934233297b8..6b8563f8e14 100644
--- a/addons/stock/models/stock_move.py
+++ b/addons/stock/models/stock_move.py
@@ -1842,7 +1842,7 @@ Please change the quantity done or the rounding precision of your unit of measur
     def _prepare_move_split_vals(self, qty):
         vals = {
             'product_uom_qty': qty,
-            'procure_method': 'make_to_stock',
+            'procure_method': self.procure_method,
             'move_dest_ids': [(4, x.id) for x in self.move_dest_ids if x.state not in ('done', 'cancel')],
             'move_orig_ids': [(4, x.id) for x in self.move_orig_ids],
             'origin_returned_move_id': self.origin_returned_move_id.id,