Add payment to invoice

POST/api/v1/invoices/{invoice_id}/payments

Link a bank transaction as payment against an invoice. Supports split payments (one transaction paying multiple invoices) and partial payments (multiple transactions paying one invoice).

Operation ID: create_invoice_payment·View as markdown·OpenAPI slice

Authentication

Bearer token authentication. Pass your DayZero API token in the Authorization header and the target business UUID in x-business-id.

Parameters

Path

invoice_idstring · uuidrequired

Request body

Schema: InvoicePaymentRequest

transaction_idstringrequired: UUID of the bank transaction representing the payment.
amountintegerrequired: Payment amount in cents: the cash allocated from the transaction (net), which must be > 0 and <= its remaining unallocated amount. With fee_cents, amount may instead be the gross — the transaction's remaining cash plus the fee (one cent either way) — and the invoice is credited exactly amount. What the invoice is credited may not exceed its balance due: overpayments are refused.
paid_onstring · date-time: Override payment date (ISO 8601). Defaults to the transaction datetime if omitted.
fee_centsinteger: Card-processor fee withheld before this money reached the bank, in cents. The invoice is credited amount + fee_cents (or amount when it is the gross) and the fee is expensed on the deposit's own journal entry (Dr Merchant Fees), so a net deposit closes a gross invoice. The deposit must already be booked: a fee on a transaction with no journal entry is refused (BUSINESS_115).

Responses

201Successful Response

Schema: SuccessEnvelope_InvoicePaymentResponse_

successboolean
messagestring
codestring
dataapp__api__v1__schemas__invoices__invoice__InvoicePaymentResponse

400Bad Request - Invalid input

Schema: ErrorResponse

errorstringrequired: Error category: validation_error, unauthorized, forbidden, not_found, conflict, rate_limited, server_error, or service_unavailable.
messagestringrequired: Human-readable explanation, safe to show to end users.
codestringrequired: Stable machine-readable code in CATEGORY_NNN form (e.g. NOT_FOUND_006, AUTH_010, GEN_002).
request_idstring: Correlation id for support requests. Echoes the x-request-id request header when one was supplied.
errorsobject: Field-level validation messages keyed by field name. Present on 400/422 validation failures only.

401Unauthorized - Missing or expired token, an MCP OAuth token used against the REST API, or no access to this business

Schema: ErrorResponse

errorstringrequired: Error category: validation_error, unauthorized, forbidden, not_found, conflict, rate_limited, server_error, or service_unavailable.
messagestringrequired: Human-readable explanation, safe to show to end users.
codestringrequired: Stable machine-readable code in CATEGORY_NNN form (e.g. NOT_FOUND_006, AUTH_010, GEN_002).
request_idstring: Correlation id for support requests. Echoes the x-request-id request header when one was supplied.
errorsobject: Field-level validation messages keyed by field name. Present on 400/422 validation failures only.

403Forbidden - Insufficient permissions

Schema: ErrorResponse

errorstringrequired: Error category: validation_error, unauthorized, forbidden, not_found, conflict, rate_limited, server_error, or service_unavailable.
messagestringrequired: Human-readable explanation, safe to show to end users.
codestringrequired: Stable machine-readable code in CATEGORY_NNN form (e.g. NOT_FOUND_006, AUTH_010, GEN_002).
request_idstring: Correlation id for support requests. Echoes the x-request-id request header when one was supplied.
errorsobject: Field-level validation messages keyed by field name. Present on 400/422 validation failures only.

404Not Found - Resource does not exist

Schema: ErrorResponse

errorstringrequired: Error category: validation_error, unauthorized, forbidden, not_found, conflict, rate_limited, server_error, or service_unavailable.
messagestringrequired: Human-readable explanation, safe to show to end users.
codestringrequired: Stable machine-readable code in CATEGORY_NNN form (e.g. NOT_FOUND_006, AUTH_010, GEN_002).
request_idstring: Correlation id for support requests. Echoes the x-request-id request header when one was supplied.
errorsobject: Field-level validation messages keyed by field name. Present on 400/422 validation failures only.

422Validation Error

Schema: ErrorResponse

errorstringrequired: Error category: validation_error, unauthorized, forbidden, not_found, conflict, rate_limited, server_error, or service_unavailable.
messagestringrequired: Human-readable explanation, safe to show to end users.
codestringrequired: Stable machine-readable code in CATEGORY_NNN form (e.g. NOT_FOUND_006, AUTH_010, GEN_002).
request_idstring: Correlation id for support requests. Echoes the x-request-id request header when one was supplied.
errorsobject: Field-level validation messages keyed by field name. Present on 400/422 validation failures only.

Code samples

POST/api/v1/invoices/{invoice_id}/payments

bash

curl -X POST 'https://api.ondayzero.com/api/v1/invoices/{invoice_id}/payments' \
  -H 'Authorization: Bearer dz_your_token' \
  -H 'x-business-id: YOUR_BUSINESS_ID' \
  -H 'Content-Type: application/json' \
  -d '{
  "amount": 12000,
  "transaction_id": "019ab37c-7801-7000-8000-000000000001"
}'