diff --git a/wizard/pos_export_bc_wizard.py b/wizard/pos_export_bc_wizard.py
index 509b63e..a39208c 100644
--- a/wizard/pos_export_bc_wizard.py
+++ b/wizard/pos_export_bc_wizard.py
@@ -110,7 +110,7 @@ class PosExportBcWizard(models.TransientModel):
                 table_customer = table or floating_order_name or customer
                 invoice = order.pos_reference or order.name
                 
-                subtotal = sum(l.price_subtotal for l in order.lines)
+                subtotal = sum(l.price_subtotal for l in order.lines if l.price_unit >= 0)
                 discount_order = sum(abs(l.price_subtotal) for l in order.lines if l.price_unit < 0)
                 tax = order.amount_tax
                 paid = sum(p.amount for p in order.payment_ids if p.amount > 0)