diff --git a/modules/purchase_trade/lot.py b/modules/purchase_trade/lot.py
index 2fdd0a6..408ffb0 100755
--- a/modules/purchase_trade/lot.py
+++ b/modules/purchase_trade/lot.py
@@ -4284,8 +4284,8 @@ class ContractDetail(ModelView):
     quantity = fields.Numeric("Quantity",digits=(1,5), required=True)
     unit = fields.Many2One('product.uom',"Unit", required=True)
     qt_unit = fields.Many2One('product.uom',"Unit")
-    tol_min = fields.Numeric("Tol - in %", required=True)
-    tol_max = fields.Numeric("Tol + in %", required=True)
+    tol_min = fields.Numeric("Tol - in %")
+    tol_max = fields.Numeric("Tol + in %")
     crop = fields.Many2One(
         'purchase.crop', "Crop",
         states={'invisible': Eval('company_visible')})
@@ -4400,12 +4400,18 @@ class ContractDetail(ModelView):
         lqt = cls._get_lqt_from_context()
         return getattr(lqt.lot_p.line.purchase if lqt.lot_p else lqt.lot_s.sale_line.sale, 'tol_min', None) if lqt else None
 
-    @classmethod
-    def default_tol_max(cls):
-        lqt = cls._get_lqt_from_context()
-        return getattr(lqt.lot_p.line.purchase if lqt.lot_p else lqt.lot_s.sale_line.sale, 'tol_max', None) if lqt else None
-
-    @classmethod
+    @classmethod
+    def default_tol_max(cls):
+        lqt = cls._get_lqt_from_context()
+        return getattr(lqt.lot_p.line.purchase if lqt.lot_p else lqt.lot_s.sale_line.sale, 'tol_max', None) if lqt else None
+
+    @fields.depends('party', '_parent_party.tol_min', '_parent_party.tol_max')
+    def on_change_party(self):
+        if self.party:
+            self.tol_min = self.party.tol_min
+            self.tol_max = self.party.tol_max
+
+    @classmethod
     def default_del_period(cls):
         lqt = cls._get_lqt_from_context()
         if lqt and getattr(lqt.lot_p.line.purchase if lqt.lot_p else lqt.lot_s.sale_line.sale, 'del_period', None):
diff --git a/modules/purchase_trade/service.py b/modules/purchase_trade/service.py
index 236abb6..ef7cbdc 100644
--- a/modules/purchase_trade/service.py
+++ b/modules/purchase_trade/service.py
@@ -50,8 +50,8 @@ class ContractFactory:
             contract.currency = int(parts[0]) or 1
             contract.party = c.party
             contract.crop = c.crop
-            contract.tol_min = c.tol_min
-            contract.tol_max = c.tol_max
+            contract.tol_min = cls._get_tolerance(c, 'tol_min')
+            contract.tol_max = cls._get_tolerance(c, 'tol_max')
             contract.payment_term = c.payment_term
             contract.reference = c.reference
             contract.from_location = c.from_location
@@ -181,8 +181,21 @@ class ContractFactory:
             line.to_del = getattr(source_line, 'to_del', None)
             return
         line.del_period = c.del_period
-        line.from_del = c.from_del
-        line.to_del = c.to_del
+        line.from_del = (
+            c.from_del
+            or getattr(getattr(c, 'del_period', None), 'beg_date', None))
+        line.to_del = (
+            c.to_del
+            or getattr(getattr(c, 'del_period', None), 'end_date', None))
+
+    @staticmethod
+    def _get_tolerance(contract_detail, field):
+        value = getattr(contract_detail, field, None)
+        if value is not None:
+            return value
+        party = getattr(contract_detail, 'party', None)
+        value = getattr(party, field, None)
+        return value if value is not None else Decimal(0)
 
     @staticmethod
     def _normalize_quantity(quantity):
diff --git a/modules/purchase_trade/tests/test_module.py b/modules/purchase_trade/tests/test_module.py
index 01c7aac..8737c1b 100644
--- a/modules/purchase_trade/tests/test_module.py
+++ b/modules/purchase_trade/tests/test_module.py
@@ -2707,6 +2707,30 @@ class PurchaseTradeTestCase(ModuleTestCase):
         with self.assertRaises(UserError):
             ContractFactory._validate_requested_quantity(contracts, sources, ct)
 
+    def test_contract_factory_uses_party_tolerance_when_line_is_empty(self):
+        'create contracts falls back to counterparty tolerance'
+        party = Mock(tol_min=Decimal('2'), tol_max=Decimal('5'))
+        contract_detail = Mock(party=party, tol_min=None, tol_max=None)
+
+        self.assertEqual(
+            ContractFactory._get_tolerance(contract_detail, 'tol_min'),
+            Decimal('2'))
+        self.assertEqual(
+            ContractFactory._get_tolerance(contract_detail, 'tol_max'),
+            Decimal('5'))
+
+    def test_contract_factory_delivery_dates_fallback_to_period(self):
+        'hidden delivery dates are still derived from delivery period'
+        period = Mock(beg_date='2026-05-01', end_date='2026-05-31')
+        contract_detail = Mock(
+            del_period=period, from_del=None, to_del=None)
+        line = Mock()
+
+        ContractFactory._apply_delivery(line, contract_detail, {})
+
+        self.assertEqual(line.from_del, '2026-05-01')
+        self.assertEqual(line.to_del, '2026-05-31')
+
     def test_lot_matching_rejects_purchase_quantity_above_available(self):
         'apply matching cannot consume more than available purchase quantity'
         class LotQtMock:
diff --git a/modules/purchase_trade/view/contract_detail_tree.xml b/modules/purchase_trade/view/contract_detail_tree.xml
index 205f48d..67b318f 100755
--- a/modules/purchase_trade/view/contract_detail_tree.xml
+++ b/modules/purchase_trade/view/contract_detail_tree.xml
@@ -6,8 +6,6 @@
    <!-- <field name="unit"/> -->
    <field name="quantity"/>
    <field name="qt_unit"/>
-   <field name="tol_min"/>
-   <field name="tol_max"/>
    <field name="price_type"/>
    <field name="from_location"/>
    <field name="to_location"/>
@@ -15,8 +13,6 @@
    <field name="incoterm"/>
    <field name="crop"/>
    <field name="del_period"/>
-   <field name="from_del"/>
-   <field name="to_del"/>
    <field name="category" tree_invisible="1"/>
    <field name="company_visible" tree_invisible="1"/>
 </tree>