> ## Documentation Index > Fetch the complete documentation index at: https://docs.getcarbon.co/llms.txt > Use this file to discover all available pages before exploring further. # Merchant Fee Charge > Process a merchant fee charge by debiting a source account and crediting a target account. ## Overview This endpoint processes a merchant fee charge by debiting a source account and crediting a target account for the specified amount. ### Request **Method:** `POST` **URL:** `/v1/payouts/merchant-fee-charge` #### Parameters | Name | In | Type | Required | Description | | -------------- | ------ | -------- | -------- | --------------------------- | | `x-carbon-key` | Header | `string` | Yes | API key for authentication. | #### Request Body | Field | Type | Required | Description | | ----------------- | ------ | -------- | -------------------------------------------------- | | `amount` | number | Yes | Amount in Naira. Must be a positive value. | | `sourceAccountId` | string | Yes | Source account number to be debited. | | `targetAccountId` | string | Yes | Target account number to be credited. | | `description` | string | No | Optional narration/description for the fee charge. | ```json theme={null} { "amount": 10, "description": "Fee Charge of N100", "sourceAccountId": "0340899287", "targetAccountId": "6009490194" } ``` ### Response **Status Code:** `201 Created` **Content-Type:** `application/json` #### Example Response ```json theme={null} { "status": "success", "message": "Merchant fee charge processed successful...", "data": { "success": true, "message": "Successful", "statusCode": "00", "transaction": { "wasReversed": false, "amount": 1000, "description": "Fee Charge of N100", "category": "Fund Transfer", "uniqueRef": "177383661255062352", "internalRef": "1406812", "transactionType": "DEBIT", "entryDate": "2026-03-18T12:23:41.015+0000", "internal": true, "accountId": "0340899287" } } } ``` #### Response Fields | Field | Type | Description | | ---------------------------------- | ------- | ------------------------------------------------- | | `status` | string | Overall request status (`success`) | | `message` | string | Human-readable result message | | `data.success` | boolean | Whether the fee charge was processed successfully | | `data.statusCode` | string | Business status code (`00` = success) | | `data.transaction.uniqueRef` | string | Unique transaction reference for reconciliation | | `data.transaction.internalRef` | string | Internal reference for support lookups | | `data.transaction.amount` | number | Amount processed (in kobo) | | `data.transaction.transactionType` | string | Direction of the transaction (`DEBIT`) | | `data.transaction.accountId` | string | The source account that was debited | `data.statusCode: "00"` indicates a successful transaction. Use `data.transaction.uniqueRef` and `data.transaction.internalRef` for reconciliation and support. ### Error Responses **Status Code:** `400 Bad Request` A 400 response indicates the request was invalid — for example, missing required fields, invalid account identifiers, or an invalid amount. ```json theme={null} { "status": "failed", "message": "invalid source account" } ``` ## OpenAPI ````yaml POST /v1/payouts/merchant-fee-charge openapi: 3.0.0 info: title: Carbon Business API description: >- ## Welcome to our API Developer Documentation Carbon aims to unlock the full potential of your business with a feature-rich account designed for growth. ## Integrations We aim to provide our APIs for developers and businesses to offer financial services to their existing customer base through REST APIs without doing the heavy lifting. Our API has predictable resource-oriented URLs, accepts form-encoded request bodies, returns JSON-encoded responses, and uses standard HTTP response codes, authentication, and verbs. ### Authentication `Authorization : API Key` Header `x-carbon-key : value` `x-carbon-key` can be generated via developer page on Carbon Business | Environment | URL | | --- | --- | | Live | | | Sandbox | [https://carbonapistagingsecure.getcarbon.co/baas/api](https://carbonapistagingsecure.getcarbon.co/baas/api) | ### **Handling Errors** We use the conventional HTTP response codes to indicate the success or failure of an API request. Codes in the 2xx range indicate success. Codes in the 4xx range indicate an error that failed given the information provided (e.g., a required parameter was omitted, etc.). Codes in the 5xx range indicate an error with our servers. | Error | Description | | --- | --- | | 400 - Bad Request | The request was unacceptable, often due to missing a required parameter. | | 401 - Unauthorized | Not a valid API key was provided. | | 402 - Request Failed | The parameters were valid but the request failed. | | 403 - Forbidden | The API key doesn't have permission to perform the request. | | 404 - Not Found | The requested resource doesn't exist. | | 429 - Too Many Requests | Too many requests hit the API | | 500, 502, 503, 504 - Server Errors | System Error | version: 1.0.0 servers: - url: https://carbonapistagingsecure.getcarbon.co/baas/api description: >- Replace {{base_url}} with your API base URL (e.g., https://api.example.com) security: - apikeyAuth: [] tags: - name: Accounts description: >- Virtual accounts are generated account details (account number and bank) that allow Carbon Business merchants to receive payments from customers via NGN bank transfer. This is currently only available in naira (NGN). Virtual accounts are either dynamic (temporary) or static (permanent). A dynamic account number expires after handling a transaction, while a static account number doesn't expire. **Static Account** Creating static accounts can be useful when receiving recurring payments through bank transfers. The process involves generating a static virtual account with customer information. Once payment is made, we will send you a webhook notification, which you can then manage. **Dynamic Account** Creating dynamic accounts can be useful when receiving one-time payments through bank transfers. The process involves generating a dynamic virtual account with a set amount for the customer during checkout. Once payment is made, we will send you a webhook notification, which you can then manage. Key things you can do with these endpoints: - Create an account - Retreive an account - Verify Transaction - Retreive a list of transactions - name: Accounts > Transactions - name: Banks description: |- - Get a list of banks and financial institutions - Verify/resolve account details - name: Customers description: >- This collection contains a set of API endpoints to manage customer-related operations for an application. The endpoints allow for creating a new customer, retrieving a list of all customers, and fetching details of a single customer. - Create Customer - Fetch Customer/Customers - name: Payout description: |- - Make Transfer - Verify Transfer - name: Status description: '- Service Health check' - name: Verification - name: Webhook description: |- ## EVENTS `account.incoming-transaction` ``` json { "event": "account.incoming-transaction", "data": { "id": "string", "amount": "float", "currency": "string", "transactionType": "string", "entryDate": "datetime", "uniqueRef": "string", "account": { "id": "string", "bankAccount": { "accountName": "string", "accountNumber": "string", "bank": { "code": "string", "name": "string" } }, "static": boolean, "currency": "string", "clientId": "string" } } } ``` `account.outgoing-transaction` ``` json { "event": "account.outgoing-transaction", "data": { "id": "string", "amount": "float", "currency": "string", "transactionType": "string", "entryDate": "datetime", "uniqueRef": "string", "account": { "id": "string", "bankAccount": { "accountName": "string", "accountNumber": "string", "bank": { "code": "string", "name": "string" } }, "static": boolean, "currency": "string", "clientId": "string" } } } ``` - name: Loans description: >- Partner lending API. Enables fintech partners to originate business loans for their end-customers. - Enroll customers for lending and trigger KYC - Submit loan applications and supporting documents - Manage offer acceptance, disbursement account, and post-offer steps - Charge repayments and retrieve repayment schedules paths: /v1/payouts/merchant-fee-charge: post: tags: - Payout summary: Merchant Fee Charge description: >- Processes a merchant fee charge by debiting a source account and crediting a target account for the specified amount. ### Request Body - `amount` (number, required): Amount in Naira. Must be a positive value. - `sourceAccountId` (string, required): Source account number to be debited. - `targetAccountId` (string, required): Target account number to be credited. - `description` (string, optional): Narration/description for the fee charge. ### Response - `status` (string): Overall request status. - `message` (string): Human-readable result message. - `data.success` (boolean): Whether the fee charge was processed successfully. - `data.statusCode` (string): Business status code (`00` = success). - `data.transaction.uniqueRef` (string): Unique transaction reference for reconciliation. - `data.transaction.internalRef` (string): Internal reference for support lookups. - `data.transaction.amount` (number): Amount processed. - `data.transaction.transactionType` (string): Direction of the transaction (e.g., `DEBIT`). - `data.transaction.accountId` (string): The source account number that was debited. parameters: - name: x-carbon-key in: header schema: type: string required: true example: '{{access_token}}' requestBody: description: Provide the required values for the request body. required: true content: application/json: schema: type: object required: - amount - sourceAccountId - targetAccountId properties: amount: type: number description: Amount in Naira. Must be a positive value. example: 10 sourceAccountId: type: string description: Source account number to be debited. example: '0340899287' targetAccountId: type: string description: Target account number to be credited. example: '6009490194' description: type: string description: Optional narration/description for the fee charge. example: Fee Charge of N100 example: amount: 10 description: Fee Charge of N100 sourceAccountId: '0340899287' targetAccountId: '6009490194' responses: '201': description: Created content: application/json: schema: type: object example: status: success message: Merchant fee charge processed successful... data: success: true message: Successful statusCode: '00' transaction: wasReversed: false amount: 1000 description: Fee Charge of N100 category: Fund Transfer uniqueRef: '177383661255062352' internalRef: '1406812' transactionType: DEBIT entryDate: 2026-03-18T12:23:41.015+0000 internal: true accountId: '0340899287' '400': description: Bad Request content: application/json: schema: type: object example: status: failed message: invalid source account components: securitySchemes: apikeyAuth: type: apiKey in: header name: apikey description: Provide your API key in the 'apikey' header. ````