---
title: "Update a bill · Bills · COUNT Partner API"
description: "Updates a bill. Only the fields you send are changed. PATCH /partners/bills/{uuid}"
canonical: "https://developers.getcount.com/reference/bills/update-bill"
source: "https://developers.getcount.com/reference/bills/update-bill"
---
[Bills](https://developers.getcount.com/reference/bills) / Update a bill

# Update a bill

PATCH `/partners/bills/{uuid}`

Updates a bill. Only the fields you send are changed.

Same UUID field names as create. Providing lineItems replaces all lines. Approved or paid bills restrict which fields can change.

HMAC signature + Bearer access token

[Try this request](https://developers.getcount.com/tools/try-it?method=PATCH&path=%2Fpartners%2Fbills%2F%7Buuid%7D&body=%7B%0A++%22dueDate%22%3A+%222026-03-01%22%2C%0A++%22notes%22%3A+%22Extended+payment+terms%22%0A%7D)

[Transactions API](https://developers.getcount.com/reference/transactions) [Vendors API](https://developers.getcount.com/reference/vendors) [Chart of Accounts API](https://developers.getcount.com/reference/chart-of-accounts)

#### Path parameters

`uuid` uuid required

The bill UUID to update.

#### Request body

`vendorUuid` uuid

Updated vendor UUID.

`date` date

Updated bill date.

`dueDate` date

Updated due date.

`billNumber` string

Updated bill number.

`purchaseOrderNumber` string

Updated PO number.

`notes` string

Updated notes.

`currency` string

Updated currency code.

`lineItems` array

Replacement line items (same shape as create).

`tagUuids` array

Replacement tag UUID list.

`projectUuid` uuid

Updated project UUID.

#### Responses

`200` Bill updated successfully.

`400` Change not allowed on approved or paid bill.

`404` Bill not found.

`401` Missing or invalid HMAC signature, expired timestamp, or invalid Bearer token. [Troubleshoot](https://developers.getcount.com/getting-started/errors#error-401)

`403` The credential does not have access to this workspace or resource. [Troubleshoot](https://developers.getcount.com/getting-started/errors#error-403)

`429` Rate limit exceeded (100 requests per minute per clientId). Retry after the Retry-After header. [Troubleshoot](https://developers.getcount.com/getting-started/errors#error-429)

[Previous POST Create a bill](https://developers.getcount.com/reference/bills/create-bill) [Next DELETE Delete a bill](https://developers.getcount.com/reference/bills/delete-bill)

PATCH `https://api.getcount.com/partners/bills/{uuid}`

Request

```javascript
import crypto from 'node:crypto';

const BASE_URL = 'https://api.getcount.com';
const CLIENT_ID = process.env.COUNT_CLIENT_ID;
const CLIENT_SECRET = process.env.COUNT_CLIENT_SECRET;
const ACCESS_TOKEN = process.env.COUNT_ACCESS_TOKEN;

const method = 'PATCH';
const signingPath = '/bills/3fa85f64-5717-4562-b3fc-2c963f66afa6';
const timestamp = Math.floor(Date.now() / 1000).toString();
const body = {
  "dueDate": "2026-03-01",
  "notes": "Extended payment terms"
};
const bodyString = JSON.stringify(body);

const bodyHash = crypto.createHash('sha256').update(bodyString).digest('hex');
const baseString = `${method}:${signingPath}:${timestamp}:${bodyHash}`;
const signature = crypto.createHmac('sha256', CLIENT_SECRET).update(baseString).digest('hex');

const response = await fetch(`${BASE_URL}/partners/bills/3fa85f64-5717-4562-b3fc-2c963f66afa6`, {
  method,
  headers: {
    'x-client-id': CLIENT_ID,
    'x-timestamp': timestamp,
    'x-signature': signature,
    'Content-Type': 'application/json',
    Authorization: `Bearer ${ACCESS_TOKEN}`,
  },
  body: bodyString,
});

console.log(await response.json());
```

Response · 200

```json
{
  "status": "success",
  "message": "Bill updated successfully",
  "data": {
    "id": "b2c3d4e5-f6a7-8901-bcde-f23456789012",
    "billNumber": "BILL-1042",
    "billType": "bill",
    "date": "2026-01-15",
    "dueDate": "2026-03-01",
    "currency": "USD",
    "approvalStatus": "approved",
    "status": "unpaid",
    "total": 250,
    "paidAmount": 0,
    "amountDue": 250,
    "notes": "Extended payment terms",
    "purchaseOrderNumber": null,
    "isDeleted": false,
    "vendor": {
      "id": "f1a2b3c4-d5e6-7890-abcd-ef1234567890",
      "name": "Office Depot",
      "email": "ap@officedepot.example"
    },
    "lineItems": [
      {
        "id": "a4b5c6d7-e8f9-0123-abcd-456789012345",
        "description": "Office supplies",
        "quantity": 1,
        "price": 250,
        "total": 250,
        "categoryAccountUuid": "c3d4e5f6-a7b8-9012-cdef-123456789012"
      }
    ],
    "transactions": [],
    "appliedVendorMemos": [],
    "tagUuids": [],
    "createdAt": "2026-01-15T10:30:00.000Z",
    "updatedAt": "2026-01-28T14:22:30.000Z"
  }
}
```