| UUID | uuid | string | | Universally Unique Identifier. |
| Date | date | cal.Date | | When the advance was made. |
| Key | key | cbc.Key | | The payment means used to make the advance. |
| Reference | ref | string | | ID or reference for the advance. |
| Grant | grant | boolean | | If this “advance” payment has come from a public grant or subsidy, set this to true. |
| Description | description | string | true | Details about the advance. |
| Percent | percent | num.Percentage | | Percentage of the total amount payable that was paid. Note that multiple advances with percentages may lead to rounding errors, especially when the total advances sums to 100%. We recommend only including one advance with a percent value per document. |
| Amount | amount | num.Amount | true | How much was paid. |
| Currency | currency | currency.Code | | If different from the parent document’s base currency. |
| Card | card | pay.Card | | Details of the payment that was made via a credit or debit card. |
| Credit Transfer | credit_transfer | pay.CreditTransfer | | Details about how the payment was made by credit (bank) transfer. |
| Extensions | ext | tax.Extensions | | Tax extensions required by tax regimes or addons. |
| Meta | meta | cbc.Meta | | Additional details useful for the parties involved. |