# PATCH /api/v1/bills/{bill_id}/payment-initiation

> Mark or clear bill payment-initiated

- **Tag:** bills
- **Operation ID:** `set_bill_payment_initiation`

## Description

Track money in flight: mark that payment was initiated outside DayZero (e.g. a bank with no API) before the bank transaction exists to reconcile against.

## Authentication

Bearer token in `Authorization` header.
Required header: `x-business-id: <business uuid>`.

## Parameters

- `bill_id` (path, string, required)

## Request body

Schema: `BillPaymentInitiationRequest`

- `initiated` (boolean · required) — True to mark payment initiated; False to clear the marker.
- `initiated_on` (string · date-time) — When the payment was initiated. Defaults to now when marking.

## Example request

```json
{
  "initiated": true,
  "initiated_on": "2026-02-20T15:30:00Z"
}
```

## Responses

### 200 — Successful Response

Schema: `SuccessEnvelope_BillResponse_`

- `success` (boolean)
- `message` (string)
- `code` (string)
- `data` (BillResponse)

### 400 — Bad Request - Invalid input

Schema: `ErrorResponse`

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

### 401 — Unauthorized - Missing/invalid token or no access to this business

Schema: `ErrorResponse`

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

### 403 — Forbidden - Insufficient permissions

Schema: `ErrorResponse`

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

### 404 — Not Found - Resource does not exist

Schema: `ErrorResponse`

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

### 422 — Validation Error

Schema: `ErrorResponse`

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

## Code samples

### cURL

```bash
curl -X PATCH 'https://api.ondayzero.com/api/v1/bills/{bill_id}/payment-initiation' \
  -H 'Authorization: Bearer dz_your_token' \
  -H 'x-business-id: YOUR_BUSINESS_ID' \
  -H 'Content-Type: application/json' \
  -d '{
  "initiated": true,
  "initiated_on": "2026-02-20T15:30:00Z"
}'
```

### JavaScript

```javascript
const response = await fetch('https://api.ondayzero.com/api/v1/bills/{bill_id}/payment-initiation', {
  method: 'PATCH',
  headers: {
    Authorization: 'Bearer dz_your_token',
    'x-business-id': 'YOUR_BUSINESS_ID',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
  "initiated": true,
  "initiated_on": "2026-02-20T15:30:00Z"
}),
});
const data = await response.json();
```

### Python

```python
import httpx

headers = {
    "Authorization": "Bearer dz_your_token",
    "x-business-id": "YOUR_BUSINESS_ID",
}

payload = {'initiated': True, 'initiated_on': '2026-02-20T15:30:00Z'}

response = httpx.patch("https://api.ondayzero.com/api/v1/bills/{bill_id}/payment-initiation", headers=headers, json=payload)
data = response.json()
```

## See also

- HTML version: https://www.ondayzero.com/docs/reference/bills/set-bill-payment-initiation
- OpenAPI slice: https://www.ondayzero.com/docs/reference/bills/set-bill-payment-initiation/openapi.json
- Other endpoints in **bills**: https://www.ondayzero.com/docs/reference/bills (markdown bundle: https://www.ondayzero.com/docs/reference/bills.md, OpenAPI: https://www.ondayzero.com/docs/reference/bills/openapi.json)
- Endpoint catalog: https://www.ondayzero.com/docs/reference/index.md