| Connected Account | The connected account to use for the request | Connected Account | Yes | |
| Account ID | | Text (Short) | Yes | |
| Invoice ID | The ID of the invoice want to update | Text (Short) | Yes | |
| Client ID | The ID of the retainer associated with this invoice | Text (Short) | No | |
| Currency | The currency used by the invoice. If not provided, the client’s currency will be used. See a list of supported currencies | Text (Short) | No | |
| Discount | This percentage is subtracted from the subtotal. Example: use 10.0 for 10.0% | Text (Short) | No | |
| Due date | Date the invoice is due. Defaults to the issue_date if no payment_term is specified | Date | No | |
| Estimate ID | The ID of the estimate associated with this invoice | Text (Short) | No | |
| Issue date | Date the invoice was issued. Defaults to today’s date | Date | No | |
| Notes | Notes about the project | Text (Long) | No | |
| Number | If no value is set, the number will be automatically generated | Text (Short) | No | |
| Payment term | The timeframe in which the invoice should be paid. Defaults to custom. Options: upon receipt, net 15, net 30, net 45, or net 60 | Text (Short) | No | |
| Purchase order | The purchase order number | Text (Short) | No | |
| Retainer ID? | The ID of the retainer associated with this invoice | True/False | No | |
| Subject | The invoice subject | Text (Short) | No | |
| Tax | This percentage is applied to the subtotal, including line items and discounts. Example: use 10.0 for 10.0% | Text (Short) | No | |
| Tax 2 | This percentage is applied to the subtotal, including line items and discounts. Example: use 10.0 for 10.0% | Text (Short) | No | |