This field captures an invoice subtotal amount and it forms part of the invoice Total.

This field is usually not mandatory, but the system converts any extracted value to a valid amount using a period as a decimal separator. The system uses this value in the validation calculation applied against all amount fields. It uses the following formula:

Invoice Total = line item total + total tax + freight + miscellaneous charge – discount – withholding tax – ISR Retention

If line items are not mandatory and are not captured, then the amount fields are calculated with the following formula:

Invoice Total = SubTotal + total tax + freight + miscellaneous charge – discount – withholding tax – ISR Retention

Where Total Tax is the total amount of all taxes on the document. This can include Tax Amount and any other country-specific tax fields.

And Net Amount is either SubTotal or the sum of NetAmount0 - NetAmount4 if VAT-based tax processing is enabled.

The tolerance for these calculations is configured in the Settings > Invoice Processing > Global Settings > Tolerance Settings. The system applies this tolerance based on the tolerance group linked to the currency of the invoice.