How to apply a discount at the item level and globally?

Tip

Last updated on 2025-08-27.

A discount can be applied at the item level or globally. Below is an example for each case:

 

Item discount

Line-item discounts are applied directly to each item. When a discount is present the full_amount is calculated as follows:   full_amount = ((unit_amount - discount) * quantity) + VAT   The discount is applied per unit, excluding VAT.

{
   "content": {
       "type": "SIMPLIFIED",
       "number": "E-3",
       "text": "Factura de venta de prendas de vestir",
       "full_amount": "50.45",
       "items": [
           {
               "text": "Sombrero",
               "quantity": "3",
               "unit_amount": "16.52",
               "full_amount": "45.45",
               "discount":"4.00",
               "system": {
                   "type": "REGULAR",
                   "category": {
                       "type": "VAT"
                   }
               }
           },
           {
               "text": "Bufanda",
               "quantity": "1",
               "unit_amount": "4.13",
               "full_amount": "5",
               "system": {
                   "type": "REGULAR",
                   "category": {
                       "type": "VAT"
                   }
               }
           }
       ]
   },
   "metadata": {
       "metadata1": "metadata1",
       "metadata2": "metadata2"
   }
}

Global discount

Global discounts must be included as an additional line in the invoice, with a negative amount.

{
    "content": {
        "type": "SIMPLIFIED",
        "number": "E-1",
        "text": "Factura de venta de prendas de vestir",
        "full_amount": "980.10",
        "items": [
            {
                "text": "Zapatos",
                "quantity": "1",
                "unit_amount": "300.00",
                "discount": "90.00",
                "full_amount": "254.10",
                "system": {
                    "type": "REGULAR",
                    "category": {
                        "type": "VAT"
                    }
                }
            },
            {
                "text": "Chaqueta",
                "quantity": "1",
                "unit_amount": "800.0",
                "full_amount": "968.0",
                "system": {
                    "type": "REGULAR",
                    "category": {
                        "type": "VAT"
                    }
                }
            },
            {
                "text": "Discount",
                "quantity": "1",
                "unit_amount": "-200.0",
                "full_amount": "-242.0",
                "system": {
                    "type": "REGULAR",
                    "category": {
                        "type": "VAT"
                    }
                }
            }
        ]
    },
    "metadata": {
        "metadata1": "metadata1",
        "metadata2": "metadata2"
    }
}

How should a global discount be represented when multiple VAT rates apply?

A separate global discount line must be created for each VAT rate. If no VAT rate is provided, a default rate of 21% is applied.

{
   "text": "Discount",
   "quantity": "1",
   "unit_amount": "-200.0",
   "full_amount": "-242.0",
   "system": {
       "type": "REGULAR",
       "category": {
           "type": "VAT"
       }
   }
},
{
   "text": "Discount",
   "quantity": "1",
   "unit_amount": "-100.0",
   "full_amount": "-100.0",
   "system": {
       "type": "REGULAR",
       "category": {
           "type": "NO_VAT",
           "cause": "TAXABLE_EXEMPT_1"
       }
   }
}