Cross River ACH API

openapi: 3.0.3
info:
  title: Cross River Operating System (COS) Accounts ACH API
  description: 'The Cross River Operating System (COS) is a collection of RESTful APIs from Cross River Bank (an FDIC-member bank) for embedded finance and Banking-as-a-Service - deposit accounts, ACH, wires, instant payments (RTP / FedNow / CRNow), card issuing and management, lending, and customer management (KYC / onboarding). COS is organized around REST with object-oriented URLs and JSON responses, and uses OAuth 2.0 (client credentials grant) to issue a signed JWT Bearer access token that must be sent on every request.

    ACCESS MODEL: Cross River is a regulated bank and COS access is partner/enterprise-gated. Programs are onboarded via Cross River sales and a relationship manager, who provision client_id / client_secret credentials for the sandbox (https://sandbox.crbcos.com) and, after go-live, for production. The public production base URL is not published in the open documentation.

    GROUNDING NOTE: The paths, methods, and module base URLs in this document are grounded in the public Cross River developer documentation at docs.crossriver.com (as of 2026-07-12). Because the live sandbox is credential-gated, request and response BODY SCHEMAS below are MODELED representative structures, not copied from the credential-gated OpenAPI / Postman collection Cross River shares with onboarded partners. Verify exact field names and required properties against the official reference and the partner-provided collection.'
  version: '1.0'
  contact:
    name: Cross River
    url: https://www.crossriver.com/
  license:
    name: Proprietary
    url: https://www.crossriver.com/
servers:
- url: https://sandbox.crbcos.com
  description: COS sandbox host for the core modules (Core, ACH, Wires, RTP, Cards, etc.). Requires partner-provisioned OAuth2 credentials. Production host is issued separately during go-live and is not publicly documented.
- url: https://arixapisandbox.crbnj.net
  description: Lending / loan origination sandbox host (separate from the core COS host).
security:
- oauth2ClientCredentials: []
tags:
- name: ACH
  description: ACH origination and receipt (COS Payments, /ach).
paths:
  /ach/v1/payments:
    post:
      operationId: sendAchPayment
      tags:
      - ACH
      summary: Send an ACH payment
      description: Originates a single ACH payment over the Federal Reserve ACH network. Supports standard and same-day ACH. An idempotency-key header is recommended to safely retry. MODELED request body.
      parameters:
      - $ref: '#/components/parameters/IdempotencyKey'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/AchPaymentInput'
      responses:
        '200':
          description: The created ACH payment.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Payment'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '422':
          $ref: '#/components/responses/ValidationError'
components:
  responses:
    ValidationError:
      description: The request payload failed validation.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
    Unauthorized:
      description: Missing or invalid Bearer token.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
  schemas:
    AchPaymentInput:
      type: object
      description: MODELED. Verify required fields against the official reference.
      required:
      - amount
      - accountNumber
      properties:
        amount:
          type: number
        currency:
          type: string
          default: USD
        accountNumber:
          type: string
          description: The funding account number.
        counterparty:
          type: object
          additionalProperties: true
        sameDay:
          type: boolean
        secCode:
          type: string
          description: Standard Entry Class code (e.g. PPD, CCD, WEB).
    Error:
      type: object
      properties:
        error:
          type: object
          properties:
            code:
              type: string
            message:
              type: string
            details:
              type: object
              additionalProperties: true
    Payment:
      type: object
      properties:
        id:
          type: string
        status:
          type: string
        amount:
          type: number
        currency:
          type: string
        createdAt:
          type: string
          format: date-time
  parameters:
    IdempotencyKey:
      name: idempotency-key
      in: header
      required: false
      description: A client-generated UUID used to safely retry a request without duplicating it.
      schema:
        type: string
        format: uuid
  securitySchemes:
    oauth2ClientCredentials:
      type: oauth2
      description: 'OAuth 2.0 client credentials grant. POST client_id, client_secret and grant_type=client_credentials to the COS identity provider token endpoint (sandbox: https://idptest.crbcos.com/connect/token; lending uses https://oauthtest.crbnj.net/connect/token). The response is a signed JWT that must be sent as `Authorization: Bearer <token>` on every request.'
      flows:
        clientCredentials:
          tokenUrl: https://idptest.crbcos.com/connect/token
          scopes: {}