Western Alliance Bank ACH API (Beta)

openapi: 3.1.0
info:
  title: Western Alliance Bank ACH EAPI
  version: v1
  description: 'Beta. Originates an ACH batch (NACHA batch header + entry details) for credit or debit.


    Derived mechanically from the ''ACH EAPI | Beta'' Postman collection published on the WAB API Developer Portal (family:
    Transactional APIs). Every path, header, query parameter and request body comes from that collection; response bodies
    are not captured because the collection ships none.'
  contact:
    name: Western Alliance Bank API Developer Portal
    url: https://developer.westernalliancebank.com/s/
  termsOfService: https://www.westernalliancebancorporation.com/sites/default/files/2025-05/api-services-terms-conditions.pdf
  x-family: Transactional
  x-generated-from: postman
  x-source: https://developer.westernalliancebank.com/sfsites/c/cms/delivery/media/MCUYE2OVQ3XBG7HPWJCS2LVIA7UE
  x-source-page: https://developer.westernalliancebank.com/s/postman-collection
  x-provenance:
    generated: '2026-09-17'
    method: derived
    source: postman/western-alliance-bancorporation-ach-eapi-beta.postman_collection.json
    note: Mechanical Postman -> OpenAPI conversion; no operations, parameters or examples were added beyond the collection.
  x-status: beta
servers:
- url: https://api-connect.westernalliancebanktest.com
  description: Client UAT environment (all data must be fake / masked test data per the API Services Terms) — the collection
    as published targets this host (env=qa)
- url: https://api-connect.westernalliancebank.com
  description: Production (Client ID / Client Secret and token issued at Treasury Management enrollment)
tags:
- name: Get Token
- name: Healthcheck
- name: ACH Request
paths:
  /entitlements-get-token-eapi/api/v1/token:
    get:
      operationId: getToken
      summary: Get Token
      tags:
      - Get Token
      parameters:
      - name: Scope
        in: query
        required: true
        schema:
          type: string
        example: Informational
      - name: X-Correlation-Id
        in: header
        required: true
        schema:
          type: string
          format: uuid
        description: Client-generated GUID used to correlate the request across WAB systems.
      - name: X-Source-System
        in: header
        required: false
        schema:
          type: string
      - name: AppClientId
        in: header
        required: true
        schema:
          type: string
        description: Credential header (AppClientId); value issued by Western Alliance Bank at enrollment. Never publish real
          values.
      - name: AppClientSecret
        in: header
        required: true
        schema:
          type: string
        description: Credential header (AppClientSecret); value issued by Western Alliance Bank at enrollment. Never publish
          real values.
      responses:
        '200':
          description: Successful response. The published collection ships no saved response, so the response schema is not
            captured here.
      x-beta: true
  /trnsct-ach-eapi/api/v1/healthcheck:
    get:
      operationId: healthcheck
      summary: Healthcheck
      tags:
      - Healthcheck
      parameters:
      - name: X-Correlation-Id
        in: header
        required: true
        schema:
          type: string
          format: uuid
        description: Client-generated GUID used to correlate the request across WAB systems.
      - name: X-Dependent-Ping
        in: header
        required: false
        schema:
          type: string
        example: 'true'
      security:
      - bearerToken: []
      responses:
        '200':
          description: Successful response. The published collection ships no saved response, so the response schema is not
            captured here.
      x-beta: true
  /trnsct-ach-eapi/api/v1/achRequest:
    post:
      operationId: achRequestUAT
      summary: ACH Request UAT
      tags:
      - ACH Request
      parameters:
      - name: X-Correlation-Id
        in: header
        required: true
        schema:
          type: string
          format: uuid
        description: Client-generated GUID used to correlate the request across WAB systems.
      - name: X-Source-System
        in: header
        required: false
        schema:
          type: string
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              properties:
                BatchHeader:
                  type: object
                  properties:
                    StandardEntryClassCode:
                      type: string
                    DebitORCredit:
                      type: string
                    CompanyEntryDescription:
                      type: string
                    EffectiveEntryDate:
                      type: string
                    CompanyDescriptiveDate:
                      type: string
                    CompanyName:
                      type: string
                    CompanyIdentification:
                      type: string
                    OriginatingDFIIdentification:
                      type: string
                EntryDetail:
                  type: array
                  items:
                    type: object
                    properties:
                      ReceiverName:
                        type: string
                      EntryConfirmationNumber:
                        type: string
                      ReceivingAccountType:
                        type: string
                      ReceivingAccountNumber:
                        type: string
                      ReceiverRoutingNumber:
                        type: string
                      ReceiverIdentificationNumber:
                        type: string
                      Amount:
                        type: string
                      VirtualAccountName:
                        type: string
                      VirtualAccountNumber:
                        type: string
                      TraceNumber:
                        type: string
                      AddendaDetails:
                        type: string
                      PaymentTypeCode:
                        type: string
            example:
              BatchHeader:
                StandardEntryClassCode: PPD
                DebitORCredit: Credit
                CompanyEntryDescription: Payroll
                EffectiveEntryDate: '2023-06-02'
                CompanyDescriptiveDate: '2023-01-11'
                CompanyName: DDRpvtltd
                CompanyIdentification: '6340360466'
                OriginatingDFIIdentification: '12210598'
              EntryDetail:
              - ReceiverName: R
                EntryConfirmationNumber: '130656789012'
                ReceivingAccountType: '27'
                ReceivingAccountNumber: '9832523532'
                ReceiverRoutingNumber: '133756121'
                ReceiverIdentificationNumber: '111122223333121'
                Amount: '496600'
                VirtualAccountName: ''
                VirtualAccountNumber: ''
                TraceNumber: '123456989090100'
                AddendaDetails: TRN*1*12345*1512345678*999999999
                PaymentTypeCode: S
      security:
      - bearerToken: []
      responses:
        '200':
          description: Successful response. The published collection ships no saved response, so the response schema is not
            captured here.
      x-beta: true
components:
  securitySchemes:
    bearerToken:
      type: http
      scheme: bearer
      description: Bearer token returned by GET /entitlements-get-token-eapi/api/v1/token (Token API) in exchange for the
        appClientId + appClientSecret headers. Tokens are valid for a limited period (API Services Terms 6(c)(iii)).
    appClientId:
      type: apiKey
      in: header
      name: appClientId
      description: Client ID assigned by WAB at enrollment (used with appClientSecret on the token endpoint).
    appClientSecret:
      type: apiKey
      in: header
      name: appClientSecret
      description: Client Secret known only to the client and the WAB API gateway.