diff --git a/services/nginx/app/routes/orderItemsRoute.php b/services/nginx/app/routes/orderItemsRoute.php
index b306b040..69b4fe89 100644
--- a/services/nginx/app/routes/orderItemsRoute.php
+++ b/services/nginx/app/routes/orderItemsRoute.php
@@ -104,18 +104,26 @@ class orderItemsRoute
                 }
                 // Validation order for audited products:
                 // 1. If reason_code is present, run reason validation first (most specific messages).
-                // 2. If notes is provided but empty/whitespace, return "Notes is required" (skip reason).
-                // 3. Otherwise run reason validation (covers missing reason_code and invalid combos).
+                // 2. If the product requires an order-item note and notes are provided but
+                //    empty/whitespace, return "Notes is required" (the legacy message). Other products
+                //    may carry an empty notes field without rejecting the request.
+                // 3. Otherwise run reason validation (covers missing reason_code on affected products).
                 $reasonFields = ['reason_code' => null, 'reason_label_snapshot' => null, 'reason_comment' => null];
                 $reasonCodeProvided = array_key_exists('reason_code', (array)$data) || array_key_exists('order_item_reason_code', (array)$data);
 
+                $productRequiresOrderItemNote = $product->requiresOrderItemNote();
+
                 if ($reasonCodeProvided) {
                     try {
                         $reasonFields = \classes\order_item_reason_policy::validateForProduct((int)$data['product_id'], $data);
                     } catch (\InvalidArgumentException $e) {
                         $response->error($e->getMessage(), 400);
                     }
-                } elseif (array_key_exists('notes', (array)$data) && trim((string)($data['notes'] ?? '')) === '') {
+                } elseif (
+                    $productRequiresOrderItemNote
+                    && array_key_exists('notes', (array)$data)
+                    && trim((string)($data['notes'] ?? '')) === ''
+                ) {
                     $response->error('Notes is required for this product', 400);
                 } else {
                     try {
diff --git a/services/nginx/app/tests/Api/OrderItemsApiTest.php b/services/nginx/app/tests/Api/OrderItemsApiTest.php
index f30bd41e..98bea313 100644
--- a/services/nginx/app/tests/Api/OrderItemsApiTest.php
+++ b/services/nginx/app/tests/Api/OrderItemsApiTest.php
@@ -419,6 +419,79 @@ it('does not allow clearing notes for order items whose product requires notes',
         ->assertMessage('Notes is required for this product');
 });
 
+it('allows empty notes for primary products that do not require a note', function (): void {
+    api_test_covers('POST /order/items', 'validation');
+
+    $customer = api_fixtures()->createUser(['display_name' => 'Empty Notes Customer']);
+    $department = api_fixtures()->createDepartment();
+    $cashier = api_fixtures()->createUser(['display_name' => 'Empty Notes Cashier']);
+    $order = api_fixtures()->createOrder([
+        'customer_id' => $customer['customer_number'],
+        'department_id' => $department['id'],
+        'cashier_id' => $cashier['id'],
+        'reference' => 'EMPTY-NOTES',
+    ]);
+    // Primary product with requires_note = 0 and not the extraordinary chemistry product.
+    $product = api_fixtures()->createProduct([
+        'id' => 1701,
+        'name' => 'Standard Wash',
+        'price' => 929,
+        'requires_note' => 0,
+    ]);
+    $session = api_fixtures()->createUserSession(['add_order_items', 'list_order_items', 'department_access_' . $department['id']]);
+
+    $response = api_client()->post('/order/items', [
+        'order_id' => $order['id'],
+        'product_id' => $product['id'],
+        'quantity' => 1,
+        'price' => 929,
+        'notes' => '',
+    ], $session['headers']);
+
+    $response
+        ->assertStatus(200)
+        ->assertEnvelope()
+        ->assertSuccess();
+
+    expect($response->data()['product_id'] ?? null)->toBe(1701);
+    expect($response->data()['notes'] ?? null)->toBe('');
+    expect($response->data()['reason_code'] ?? 'not_set')->toBe('not_set');
+});
+
+it('still rejects empty notes for products whose requires_note flag is enabled', function (): void {
+    api_test_covers('POST /order/items', 'validation');
+
+    $customer = api_fixtures()->createUser(['display_name' => 'Notes Required Customer']);
+    $department = api_fixtures()->createDepartment();
+    $cashier = api_fixtures()->createUser(['display_name' => 'Notes Required Cashier']);
+    $order = api_fixtures()->createOrder([
+        'customer_id' => $customer['customer_number'],
+        'department_id' => $department['id'],
+        'cashier_id' => $cashier['id'],
+        'reference' => 'NOTES-REQUIRED',
+    ]);
+    $product = api_fixtures()->createProduct([
+        'id' => 1702,
+        'name' => 'Requires-Note Wash',
+        'price' => 199,
+        'requires_note' => 1,
+    ]);
+    $session = api_fixtures()->createUserSession(['add_order_items', 'list_order_items', 'department_access_' . $department['id']]);
+
+    api_client()
+        ->post('/order/items', [
+            'order_id' => $order['id'],
+            'product_id' => $product['id'],
+            'quantity' => 1,
+            'price' => 199,
+            'notes' => '   ',
+        ], $session['headers'])
+        ->assertStatus(400)
+        ->assertEnvelope()
+        ->assertSuccess(false)
+        ->assertMessage('Notes is required for this product');
+});
+
 it('returns the extraordinary chemistry product with requires_note enabled', function (): void {
     api_test_covers('GET /products', 'happy');