Western Alliance Bank

Western Alliance Bancorporation (NYSE: WAL) is a Phoenix, Arizona based super-regional bank holding company with roughly $80 billion in assets, operating through its principal subsidiary Western Alliance Bank, an Arizona state-chartered commercial bank and member FDIC that runs regional divisions including Alliance Bank of Arizona, Bank of Nevada, Bridge Bank, and Torrey Pines Bank. It is a commercial- and business-banking focused institution rather than a consumer neobank. Western Alliance runs a real first-party developer portal, the WAB API Developer Portal ("Developer Hub") at developer.westernalliancebank.com, exposing commercial Treasury Management open-banking APIs for balance and transaction information, check images, funds transfers, and stop payments. Access is partner/customer-gated: API specifications are downloaded from the Developer Hub only with WAB-issued credentials, and authentication uses OAuth2 client-credentials (Client ID, Client Secret), a Client Certificate (mTLS), and access tokens across UAT and Production environments. Its APIs are also reachable through payment-platform partners such as Modern Treasury. No public consumer FDX or CFPB Section 1033 data-access API is documented, and no OpenAPI/Swagger is publicly downloadable.

Western Alliance Bank publishes 1 API on the APIs.io network. Tagged areas include Financial Services, Banking, United States, Treasury Management, and Open Banking.

Western Alliance Bank’s developer surface includes authentication, documentation, API reference, getting-started guide, signup flow, and 10 more developer resources.

🌐 Visit website 📡 Source on GitHub

29.1/100 emerging ▬ flat Agent 14/100 human only Full breakdown ↓
scored 2026-07-27 · rubric v0.5

1 APIs

Financial ServicesBankingUnited StatesTreasury ManagementOpen BankingPaymentsCommercial Banking

Kin Score

Kin Score How this is scored →
scored 2026-07-27 · rubric v0.5

Composite quality — 29.1/100 · emerging

Contract Quality 0.0 / 25

Developer Ergonomics 9.1 / 20

Commercial Clarity 6.8 / 20

Operational Transparency 0.7 / 13

Governance 0.0 / 12

Discoverability 8.0 / 10

Agent readiness — 14/100 · human only

Machine-Readable Contract 0 / 18

Agentic Access Contract 0 / 15

MCP Server 0 / 12

Machine-Readable Auth 10 / 10

Idempotency 0 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 0 / 7

Typed Event Surface 0 / 6

Agent Skills 0 / 5

Well-Known Catalog 4 / 4

Consent & Bot Identity 0 / 3

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APIs 1

Individual APIs this provider publishes, each with its own machine-readable definition.

Get Started 3

Portal, sign-up, and the first successful call

DeveloperPortal

DeveloperPortal

GettingStarted

GettingStarted

SignUp

SignUp

Documentation 2

Reference material describing how the API behaves

Documentation

Documentation

APIReference

APIReference

Agent Surfaces 2

MCP servers, agent skills, and machine-readable catalogs

WellKnown

WellKnown

LLMsTxt

LLMsTxt

Design & Contract 1

Pagination, idempotency, versioning, errors, and events

Conformance

Conformance

Build 1

SDKs, sample code, and the tooling you integrate with

GitHubOrganization

GitHubOrganization

Access & Security 2

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

Authentication

Authentication

Commercial 2

Pricing, plans, and the legal terms of use

PrivacyPolicy

PrivacyPolicy

TermsOfService

TermsOfService

Company 2

The organization behind the API

Website

Website

LinkedIn

Source (apis.yml)

aid: western-alliance
url: https://raw.githubusercontent.com/api-evangelist/western-alliance/refs/heads/main/apis.yml
name: Western Alliance Bank
kind: company
description: 'Western Alliance Bancorporation (NYSE: WAL) is a Phoenix, Arizona based super-regional bank holding company
  with roughly $80 billion in assets, operating through its principal subsidiary Western Alliance Bank, an Arizona state-chartered
  commercial bank and member FDIC that runs regional divisions including Alliance Bank of Arizona, Bank of Nevada, Bridge
  Bank, and Torrey Pines Bank. It is a commercial- and business-banking focused institution rather than a consumer neobank.
  Western Alliance runs a real first-party developer portal, the WAB API Developer Portal ("Developer Hub") at developer.westernalliancebank.com,
  exposing commercial Treasury Management open-banking APIs for balance and transaction information, check images, funds transfers,
  and stop payments. Access is partner/customer-gated: API specifications are downloaded from the Developer Hub only with
  WAB-issued credentials, and authentication uses OAuth2 client-credentials (Client ID, Client Secret), a Client Certificate
  (mTLS), and access tokens across UAT and Production environments. Its APIs are also reachable through payment-platform partners
  such as Modern Treasury. No public consumer FDX or CFPB Section 1033 data-access API is documented, and no OpenAPI/Swagger
  is publicly downloadable.'
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
tags:
- Financial Services
- Banking
- United States
- Treasury Management
- Open Banking
- Payments
- Commercial Banking
created: '2026-07-23'
modified: '2026-07-23'
specificationVersion: '0.19'
apis:
- aid: western-alliance:wab-treasury-management-api
  name: Western Alliance Bank API (Treasury Management)
  description: Western Alliance Bank's commercial open-banking API lets approved business clients interact directly with WAB
    systems to access balance and transaction information, retrieve check images, initiate funds transfers, and place stop
    payments. Documented publicly as an open-banking capability; API specifications and endpoints are gated behind the WAB
    Developer Hub and issued credentials.
  humanURL: https://developer.westernalliancebank.com/s/
  tags:
  - Treasury Management
  - Open Banking
  - Payments
  properties:
  - type: Documentation
    url: https://developer.westernalliancebank.com/s/
  - type: Documentation
    url: https://www.westernalliancebancorporation.com/commercial/treasury-management
  - type: TermsOfService
    url: https://www.westernalliancebancorporation.com/sites/default/files/2025-05/api-services-terms-conditions.pdf
common:
- type: DomainSecurity
  url: security/western-alliance-domain-security.yml
- type: Authentication
  url: authentication/western-alliance-authentication.yml
- type: Conformance
  url: conformance/western-alliance-conformance.yml
- type: WellKnown
  url: well-known/western-alliance-well-known.yml
- type: LLMsTxt
  url: llms/western-alliance-llms.txt
- type: Website
  url: https://www.westernalliancebancorporation.com/
- type: DeveloperPortal
  url: https://developer.westernalliancebank.com/s/
- type: Documentation
  url: https://developer.westernalliancebank.com/s/
- type: APIReference
  url: https://developer.westernalliancebank.com/s/apis
- type: GettingStarted
  url: https://developer.westernalliancebank.com/s/getting-started
- type: SignUp
  url: https://developer.westernalliancebank.com/s/login
- type: GitHubOrganization
  url: https://github.com/westernalliancebank
- type: LinkedIn
  url: https://www.linkedin.com/company/western-alliance-bank
- type: PrivacyPolicy
  url: https://www.westernalliancebancorporation.com/privacy-legal-home/privacy-policy
- type: TermsOfService
  url: https://www.westernalliancebancorporation.com/sites/default/files/2025-05/api-services-terms-conditions.pdf
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com