Plata supports different tax rates, even different tax rates in the same order. When calculating the order total, tax amounts with the same tax rate are grouped and can be shown separately on an invoice document.

The tax details are stored in the data attribute on the order instance. The format is as follows:['tax_details'] = [
    [<tax_rate>, {
        'discounts': <sum of all discounts>,
        'prices': <sum of line item prices>,
        'tax_amount': <sum of line item tax amounts>,
        'tax_rate': <tax rate (redundant)>,
        'total': <sum of line item totals>,
    # Another [tax_rate, {details}] instance etc.

The PDF code in plata.reporting.order demonstrates how the tax details might be used when generating an invoice.