diff --git a/addons/stock_account/models/stock.py b/addons/stock_account/models/stock.py
index f13559a9337..5dc72f5c146 100644
--- a/addons/stock_account/models/stock.py
+++ b/addons/stock_account/models/stock.py
@@ -235,7 +235,7 @@ class StockMove(models.Model):
                 break
 
         # Update the standard price with the price of the last used candidate, if any.
-        if new_standard_price:
+        if new_standard_price and move.product_id.cost_method == 'fifo':
             move.product_id.standard_price = new_standard_price
 
         # If there's still quantity to value but we're out of candidates, we fall in the
@@ -264,29 +264,30 @@ class StockMove(models.Model):
             valued_move_lines = self.move_line_ids.filtered(lambda ml: not ml.location_id._should_be_valued() and ml.location_dest_id._should_be_valued())
             valued_quantity = sum(valued_move_lines.mapped('qty_done'))
 
-            if self.product_id.cost_method in ['fifo', 'average']:
-                price_unit = self._get_price_unit()
-                value = price_unit * (quantity or valued_quantity)
-                vals = {
-                    'price_unit': price_unit,
-                    'value': value if quantity is None or not self.value else self.value,
-                    'remaining_value': value if quantity is None else self.remaining_value + value,
-                }
-                if self.product_id.cost_method == 'fifo':
-                    vals['remaining_qty'] = valued_quantity if quantity is None else self.remaining_qty + quantity
-                self.write(vals)
-            else:  # standard
+            # Note: we always compute the fifo `remaining_value` and `remaining_qty` fields no
+            # matter which cost method is set, to ease the switching of cost method.
+            vals = {}
+            price_unit = self._get_price_unit()
+            value = price_unit * (quantity or valued_quantity)
+            vals = {
+                'price_unit': price_unit,
+                'value': value if quantity is None or not self.value else self.value,
+                'remaining_value': value if quantity is None else self.remaining_value + value,
+            }
+            vals['remaining_qty'] = valued_quantity if quantity is None else self.remaining_qty + quantity
+
+            if self.product_id.cost_method == 'standard':
                 value = self.product_id.standard_price * (quantity or valued_quantity)
-                self.write({
+                vals.update({
                     'price_unit': self.product_id.standard_price,
                     'value': value if quantity is None or not self.value else self.value,
                 })
+            self.write(vals)
         elif self._is_out():
             valued_move_lines = self.move_line_ids.filtered(lambda ml: ml.location_id._should_be_valued() and not ml.location_dest_id._should_be_valued())
             valued_quantity = sum(valued_move_lines.mapped('qty_done'))
-            if self.product_id.cost_method == 'fifo':
-                self.env['stock.move']._run_fifo(self, quantity=quantity)
-            elif self.product_id.cost_method in ['standard', 'average']:
+            self.env['stock.move']._run_fifo(self, quantity=quantity)
+            if self.product_id.cost_method in ['standard', 'average']:
                 curr_rounding = self.company_id.currency_id.rounding
                 value = -float_round(self.product_id.standard_price * (valued_quantity if quantity is None else quantity), precision_rounding=curr_rounding)
                 self.write({
diff --git a/addons/stock_account/tests/test_stockvaluation.py b/addons/stock_account/tests/test_stockvaluation.py
index 33aee80a1ca..f7e63cc9f15 100644
--- a/addons/stock_account/tests/test_stockvaluation.py
+++ b/addons/stock_account/tests/test_stockvaluation.py
@@ -2140,7 +2140,6 @@ class TestStockValuation(TransactionCase):
         move1._action_done()
 
         self.assertEqual(move1.value, 900.0)
-        self.assertEqual(move1.remaining_qty, 0.0)  # unusedin average move
 
         # Purchase 140 units @ 15.50 per unit
         move2 = self.env['stock.move'].create({
@@ -2407,7 +2406,6 @@ class TestStockValuation(TransactionCase):
         move1.quantity_done = 10.0
         move1._action_done()
         self.assertEqual(move1.value, -990.0)  # as no move out were done for this product, fallback on the standard price
-        self.assertEqual(move1.remaining_qty, 0.0)  # unused in average move
 
     def test_average_negative_3(self):
         """ Send goods that you don't have in stock but received and send some units before.
@@ -2433,7 +2431,6 @@ class TestStockValuation(TransactionCase):
         move1._action_done()
 
         self.assertEqual(move1.value, 100.0)
-        self.assertEqual(move1.remaining_qty, 0.0)  # unused in average move
 
         # send 10 products
         move2 = self.env['stock.move'].create({
@@ -2467,7 +2464,6 @@ class TestStockValuation(TransactionCase):
         move3._action_done()
 
         self.assertEqual(move3.value, -100.0)  # as no move out were done for this product, fallback on latest cost
-        self.assertEqual(move3.remaining_qty, 0.0)  # unused in average move
 
     def test_average_negative_4(self):
         self.product1.product_tmpl_id.cost_method = 'average'
@@ -2491,7 +2487,6 @@ class TestStockValuation(TransactionCase):
         move1._action_done()
 
         self.assertEqual(move1.value, 100.0)
-        self.assertEqual(move1.remaining_qty, 0.0)  # unused in average move
 
     def test_average_negative_5(self):
         self.product1.product_tmpl_id.cost_method = 'average'
@@ -2678,7 +2673,7 @@ class TestStockValuation(TransactionCase):
         # ---------------------------------------------------------------------
         # Change the production valuation to AVCO
         # ---------------------------------------------------------------------
-        self.product1.with_context(debug=True).product_tmpl_id.cost_method = 'average'
+        self.product1.product_tmpl_id.cost_method = 'average'
 
         # valuation should stay to ~240
         self.assertAlmostEqual(self.product1.stock_value, 240, delta=0.03)