# invoices.recordPayment

Record a full or partial payment on an issued invoice with amountMinor in the invoice currency, paid date, method, reference, and an optional bank transaction. Optionally write off a small remaining balance such as wire fees. Updates the balance and paid status.

`POST /api/v1/accounting/invoices.recordPayment`

Permissions: `accounting:read`, `accounting:write` · Roles: admin, finance · Idempotency key required · Send `expectedRevision`

MCP tool: `accounting_invoices_record_payment`

## Fields

| Field | Type | Required | Notes |
| --- | --- | --- | --- |
| `invoiceId` | string (ID) | Yes | The ID of the related record. |
| `expectedRevision` | integer | Yes | The record's current revision, from the last time you read it. If someone changed the record since, the request is refused with a conflict so you can reload and check before trying again. at most 9007199254740991; greater than 0. |
| `amountMinor` | string | Yes | An amount in cents (the currency's smallest unit), written as a whole-number string such as "1250" for $12.50. Matches ^\d{1,18}$. |
| `paidOn` | string | Yes |  |
| `method` | enum |  | One of: `bank_transfer`, `wire`, `interac`, `card`, `cheque`, `cash`, `pay_link`, `other`. Default `"bank_transfer"`. |
| `reference` | string |  | at most 300 characters. |
| `note` | string |  | A short note, kept with the record. at most 1000 characters. |
| `transactionId` | string (ID) |  | The ID of a bank or card transaction, from transactions.list. |
| `writeOffRemainder` | boolean |  | Default `false`. |
| `writeOffReason` | string |  | at most 300 characters. |
| `idempotencyKey` | string | Yes | Any unique text you generate once per intended change, so a retried request only happens once. Send it as the Idempotency-Key header instead if you prefer; if you send both they must match. 8–200 characters. |

## Example request

```bash
curl https://app.getoatmilk.com/api/v1/accounting/invoices.recordPayment \
  -H "Authorization: Bearer $OATMILK_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: $(uuidgen)" \
  -d '{
  "invoiceId": "4d5e6f7a-8b9c-4d0e-8f1a-2b3c4d5e6f7a",
  "expectedRevision": 3,
  "amountMinor": "1250",
  "paidOn": "2026-09-30"
}'
```

Reference page: https://app.getoatmilk.com/docs/api/invoices.recordPayment