Mono Transactions and Statements API

openapi: 3.0.1
info:
  title: Mono Account Information Transactions and Statements API
  description: Specification of the Mono open-banking API. Mono lets businesses link customer bank accounts (Connect) to read transactions, statements, identity, income, and balance, and to collect payments via DirectPay one-time transfers and Direct Debit mandates. All requests are authenticated with the secret application key supplied in the mono-sec-key header. Monetary amounts are expressed in the lowest denomination of the currency (e.g. kobo for NGN).
  termsOfService: https://mono.co/legal
  contact:
    name: Mono Support
    url: https://docs.mono.co
    email: hi@mono.co
  version: '2.0'
servers:
- url: https://api.withmono.com
  description: Mono production API
security:
- monoSecKey: []
tags:
- name: Transactions and Statements
  description: Transactions and bank statements for a linked account.
paths:
  /v2/accounts/{id}/transactions:
    get:
      operationId: getAccountTransactions
      tags:
      - Transactions and Statements
      summary: Get transactions
      description: Lists money-in and money-out transactions for a linked account, with optional filters for date range, type, narration, and pagination.
      parameters:
      - $ref: '#/components/parameters/AccountId'
      - name: start
        in: query
        description: Start date (DD-MM-YYYY) of the transaction window.
        schema:
          type: string
      - name: end
        in: query
        description: End date (DD-MM-YYYY) of the transaction window.
        schema:
          type: string
      - name: type
        in: query
        description: Filter by transaction type.
        schema:
          type: string
          enum:
          - debit
          - credit
      - name: narration
        in: query
        description: Filter by transaction narration substring.
        schema:
          type: string
      - name: paginate
        in: query
        description: Whether to paginate the results.
        schema:
          type: boolean
      - name: page
        in: query
        description: Page number when pagination is enabled.
        schema:
          type: integer
      responses:
        '200':
          description: Transaction list.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/TransactionList'
        '401':
          $ref: '#/components/responses/Unauthorized'
  /v2/accounts/{id}/statement:
    get:
      operationId: getAccountStatement
      tags:
      - Transactions and Statements
      summary: Get bank statement
      description: Retrieves the account holder's bank statement. Returns JSON by default; set output=pdf to generate a downloadable PDF statement.
      parameters:
      - $ref: '#/components/parameters/AccountId'
      - name: period
        in: query
        description: Statement period, e.g. last6months.
        schema:
          type: string
      - name: output
        in: query
        description: Response format.
        schema:
          type: string
          enum:
          - json
          - pdf
      responses:
        '200':
          description: Statement data or PDF job reference.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Statement'
        '401':
          $ref: '#/components/responses/Unauthorized'
components:
  schemas:
    TransactionList:
      type: object
      properties:
        status:
          type: string
        message:
          type: string
        data:
          type: array
          items:
            $ref: '#/components/schemas/Transaction'
        meta:
          type: object
          properties:
            total:
              type: integer
            page:
              type: integer
    Transaction:
      type: object
      properties:
        id:
          type: string
        narration:
          type: string
        amount:
          type: integer
        type:
          type: string
          enum:
          - debit
          - credit
        balance:
          type: integer
        date:
          type: string
          format: date-time
        category:
          type: string
    Error:
      type: object
      properties:
        status:
          type: string
        message:
          type: string
    Statement:
      type: object
      properties:
        status:
          type: string
        message:
          type: string
        data:
          type: object
          properties:
            account:
              type: object
            balance:
              type: integer
            transactions:
              type: array
              items:
                $ref: '#/components/schemas/Transaction'
  parameters:
    AccountId:
      name: id
      in: path
      required: true
      description: The linked account id returned by the exchange-token endpoint.
      schema:
        type: string
  responses:
    Unauthorized:
      description: Missing or invalid mono-sec-key.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
  securitySchemes:
    monoSecKey:
      type: apiKey
      in: header
      name: mono-sec-key
      description: Secret application key issued in the Mono dashboard.