diff --git a/fusion_plating/fusion_plating_configurator/__manifest__.py b/fusion_plating/fusion_plating_configurator/__manifest__.py
index 81de69aa..c6643e23 100644
--- a/fusion_plating/fusion_plating_configurator/__manifest__.py
+++ b/fusion_plating/fusion_plating_configurator/__manifest__.py
@@ -5,7 +5,7 @@
 
 {
     'name': 'Fusion Plating — Configurator',
-    'version': '19.0.23.0.0',
+    'version': '19.0.23.1.0',
     'category': 'Manufacturing/Plating',
     'summary': 'Quotation configurator with part catalog, coating configs, and formula-based pricing engine.',
     'description': """
diff --git a/fusion_plating/fusion_plating_configurator/tests/test_charge_tax_lot.py b/fusion_plating/fusion_plating_configurator/tests/test_charge_tax_lot.py
index 26604f8d..569220dc 100644
--- a/fusion_plating/fusion_plating_configurator/tests/test_charge_tax_lot.py
+++ b/fusion_plating/fusion_plating_configurator/tests/test_charge_tax_lot.py
@@ -45,23 +45,42 @@ class TestChargeTaxLot(TransactionCase):
         self.assertAlmostEqual(wiz.total_tax, 19.5, places=2)
         self.assertAlmostEqual(wiz.total_amount, 169.5, places=2)
 
-    # ----- Task 4: lot pricing -----
+    # ----- Task 4: lot pricing (order-level toggle) -----
     def test_lot_onchange_derives_unit_price(self):
-        wiz = self._make_wizard()
+        wiz = self._make_wizard(is_lot_order=True)
         line = self.env['fp.direct.order.line'].new({
             'wizard_id': wiz.id, 'quantity': 500, 'lot_total': 1000.0,
-            'is_lot_priced': True,
         })
         line._onchange_lot_pricing()
         self.assertEqual(line.unit_price, 2.0)
 
-    def test_lot_line_subtotal_uses_lot_total(self):
-        # Even if unit_price wasn't derived (onchange didn't fire), the
-        # summary subtotal uses the flat lot_total for lot-priced lines.
-        wiz = self._make_wizard(tax_id=self.tax13.id)
+    def test_lot_onchange_noop_when_not_lot_order(self):
+        # Editing lot_total on a non-lot order must NOT touch unit_price.
+        wiz = self._make_wizard()
+        line = self.env['fp.direct.order.line'].new({
+            'wizard_id': wiz.id, 'quantity': 500, 'lot_total': 1000.0,
+            'unit_price': 7.0,
+        })
+        line._onchange_lot_pricing()
+        self.assertEqual(line.unit_price, 7.0)
+
+    def test_lot_order_toggle_rederives_line_prices(self):
+        wiz = self._make_wizard()
         self.env['fp.direct.order.line'].create({
             'wizard_id': wiz.id, 'quantity': 500, 'lot_total': 1000.0,
-            'is_lot_priced': True, 'unit_price': 0.0,
+            'unit_price': 0.0,
+        })
+        wiz.is_lot_order = True
+        wiz._onchange_is_lot_order()
+        self.assertEqual(wiz.line_ids.unit_price, 2.0)
+
+    def test_lot_line_subtotal_uses_lot_total(self):
+        # On a lot order, the summary subtotal uses the flat lot_total
+        # per line (not qty × unit_price), even if unit_price is 0.
+        wiz = self._make_wizard(tax_id=self.tax13.id, is_lot_order=True)
+        self.env['fp.direct.order.line'].create({
+            'wizard_id': wiz.id, 'quantity': 500, 'lot_total': 1000.0,
+            'unit_price': 0.0,
         })
         wiz.invalidate_recordset()
         self.assertEqual(wiz.total_subtotal, 1000.0)
diff --git a/fusion_plating/fusion_plating_configurator/views/fp_express_order_views.xml b/fusion_plating/fusion_plating_configurator/views/fp_express_order_views.xml
index 634c40f2..716b9e16 100644
--- a/fusion_plating/fusion_plating_configurator/views/fp_express_order_views.xml
+++ b/fusion_plating/fusion_plating_configurator/views/fp_express_order_views.xml
@@ -233,6 +233,10 @@
                         <span><strong>OPEN</strong> open the part record</span>
                     </div>
 
+                    <div class="mb-2 d-flex align-items-center gap-2">
+                        <field name="is_lot_order" widget="boolean_toggle"/>
+                        <span><strong>Lot Order</strong> — price each line as a flat lot total (qty preserved for production)</span>
+                    </div>
                     <div class="mb-2 d-flex gap-2">
                         <button name="action_add_from_prior_so"
                                 type="object"
@@ -286,17 +290,17 @@
                                    width="120px"/>
                             <field name="internal_description" string="Internal Notes" optional="show"/>
                             <field name="quantity" string="Qty" width="55px"/>
-                            <field name="is_lot_priced" string="Lot" width="50px"/>
                             <field name="lot_total"
                                    string="Lot Total"
                                    widget="monetary"
                                    options="{'currency_field': 'currency_id'}"
+                                   column_invisible="not parent.is_lot_order"
                                    width="90px"/>
                             <field name="unit_price"
                                    string="Price"
                                    widget="monetary"
                                    options="{'currency_field': 'currency_id'}"
-                                   readonly="is_lot_priced"
+                                   readonly="parent.is_lot_order"
                                    width="80px"/>
                             <field name="line_subtotal"
                                    string="Subtotal"
diff --git a/fusion_plating/fusion_plating_configurator/wizard/fp_direct_order_line.py b/fusion_plating/fusion_plating_configurator/wizard/fp_direct_order_line.py
index 7654fe98..bdf7564d 100644
--- a/fusion_plating/fusion_plating_configurator/wizard/fp_direct_order_line.py
+++ b/fusion_plating/fusion_plating_configurator/wizard/fp_direct_order_line.py
@@ -238,20 +238,17 @@ class FpDirectOrderLine(models.Model):
         string='Unit Price',
         currency_field='currency_id',
     )
-    is_lot_priced = fields.Boolean(
-        string='Lot Price',
-        help='Price the whole quantity as a flat lot total instead of '
-             'per unit. Unit price is derived = lot total / quantity; '
-             'the quantity is preserved for production.',
-    )
     lot_total = fields.Monetary(
         string='Lot Total', currency_field='currency_id',
+        help='Flat total for the whole line quantity when the order is a '
+             'lot order. Unit price is derived = lot total / quantity; '
+             'the quantity is preserved for production.',
     )
 
-    @api.onchange('is_lot_priced', 'lot_total', 'quantity')
+    @api.onchange('lot_total', 'quantity')
     def _onchange_lot_pricing(self):
         for line in self:
-            if line.is_lot_priced and line.quantity:
+            if line.wizard_id.is_lot_order and line.quantity:
                 line.unit_price = (line.lot_total or 0.0) / line.quantity
     line_subtotal = fields.Monetary(
         string='Subtotal',
diff --git a/fusion_plating/fusion_plating_configurator/wizard/fp_direct_order_wizard.py b/fusion_plating/fusion_plating_configurator/wizard/fp_direct_order_wizard.py
index dd79c6e6..906e1313 100644
--- a/fusion_plating/fusion_plating_configurator/wizard/fp_direct_order_wizard.py
+++ b/fusion_plating/fusion_plating_configurator/wizard/fp_direct_order_wizard.py
@@ -336,6 +336,22 @@ class FpDirectOrderWizard(models.Model):
             if rec.charge_type_id and not rec.charge_amount:
                 rec.charge_amount = rec.charge_type_id.default_amount
 
+    is_lot_order = fields.Boolean(
+        string='Lot Order',
+        help='Price the order as flat lots instead of per unit. When on, '
+             'each line takes a Lot Total and the unit price is derived = '
+             'lot total / quantity; the quantity is preserved for '
+             'production. When off, lines price per unit as usual.',
+    )
+
+    @api.onchange('is_lot_order')
+    def _onchange_is_lot_order(self):
+        for rec in self:
+            if rec.is_lot_order:
+                for line in rec.line_ids:
+                    if line.quantity:
+                        line.unit_price = (line.lot_total or 0.0) / line.quantity
+
     # ---- PO status pill (computed, display-only) ----
     po_status = fields.Selection(
         [('received', 'Received'),
@@ -403,8 +419,8 @@ class FpDirectOrderWizard(models.Model):
     @api.depends(
         'line_ids.quantity',
         'line_ids.unit_price',
-        'line_ids.is_lot_priced',
         'line_ids.lot_total',
+        'is_lot_order',
         'charge_amount',
         'tooling_charge',
         'tax_id',
@@ -420,11 +436,13 @@ class FpDirectOrderWizard(models.Model):
         at action_create_order time (so it carries into the invoice).
         """
         for rec in self:
-            subtotal = sum(
-                (l.lot_total or 0.0) if l.is_lot_priced
-                else (l.quantity or 0) * (l.unit_price or 0.0)
-                for l in rec.line_ids
-            )
+            if rec.is_lot_order:
+                subtotal = sum(l.lot_total or 0.0 for l in rec.line_ids)
+            else:
+                subtotal = sum(
+                    (l.quantity or 0) * (l.unit_price or 0.0)
+                    for l in rec.line_ids
+                )
             charge = rec.charge_amount or rec.tooling_charge or 0.0
             tax_total = 0.0
             if rec.tax_id and (subtotal + charge):
@@ -858,7 +876,7 @@ class FpDirectOrderWizard(models.Model):
                 'product_uom_qty': line.quantity,
                 'price_unit': (
                     (line.lot_total / line.quantity)
-                    if line.is_lot_priced and line.quantity
+                    if self.is_lot_order and line.quantity
                     else (line.unit_price or 0.0)
                 ),
                 'x_fc_part_catalog_id': part.id,
@@ -904,7 +922,7 @@ class FpDirectOrderWizard(models.Model):
                 # NB. Odoo 19 renamed the SO line field to tax_ids.
                 'tax_ids': ([(6, 0, self.tax_id.ids)]
                             if self.tax_id else False),
-                'x_fc_is_lot_priced': line.is_lot_priced,
+                'x_fc_is_lot_priced': self.is_lot_order,
                 'x_fc_lot_total': line.lot_total or 0.0,
             }))