diff --git a/purchase_order_category/models/purchase_order.py b/purchase_order_category/models/purchase_order.py
index 8cf37763..66583f90 100644
--- a/purchase_order_category/models/purchase_order.py
+++ b/purchase_order_category/models/purchase_order.py
@@ -1,7 +1,7 @@
 # Copyright 2017-2018 Quartile Limited
 # License LGPL-3.0 or later (https://www.gnu.org/licenses/lgpl).
 
-from odoo import fields, models
+from odoo import api, fields, models
 
 
 class PurchaseOrder(models.Model):
@@ -11,3 +11,14 @@ class PurchaseOrder(models.Model):
         "purchase.category",
         "Purchase Category",
     )
+
+    @api.multi
+    def write(self, vals):
+        res = super().write(vals)
+        if "order_line" in vals or "purchase_category_id" in vals:
+            for order in self:
+                products = order.order_line.mapped("product_id")
+                products.write(
+                    {"purchase_category_id": order.purchase_category_id.id}
+                )
+        return res
diff --git a/purchase_shop/models/purchase_order.py b/purchase_shop/models/purchase_order.py
index 795bed24..cd38f84c 100644
--- a/purchase_shop/models/purchase_order.py
+++ b/purchase_shop/models/purchase_order.py
@@ -54,3 +54,17 @@ def onchange_shop_id(self):
             if picking_type_id:
                 self.picking_type_id = picking_type_id
         return {"domain": {"purchased_by_id": ids}}
+
+    @api.multi
+    def write(self, vals):
+        res = super().write(vals)
+        if "order_line" in vals or "shop_id" in vals or "purchased_by_id" in vals:
+            for order in self:
+                products = order.order_line.mapped("product_id")
+                products.write(
+                    {
+                        "shop_id": order.shop_id.id,
+                        "purchased_by_id": order.purchased_by_id.id,
+                    }
+                )
+        return res