# Diameter API

## Docs

- [Diameter API: Banking Infrastructure for Fintechs](https://diameterpay.mintlify.app/introduction.md): Diameter API gives fintechs a single REST API to onboard users, open virtual accounts, and process domestic and international wire payments.
- [Diameter API Quickstart: Your First API Call in 15 Minutes](https://diameterpay.mintlify.app/quickstart.md): Learn how to authenticate, onboard your first end user, and initiate a domestic wire payment using the Diameter API in under 15 minutes.
- [Diameter API Authentication with OAuth2 Client Credentials](https://diameterpay.mintlify.app/authentication.md): Diameter uses OAuth2 Client Credentials to issue short-lived Bearer tokens. Learn how to obtain tokens, manage scopes, and handle token expiry.
- [Diameter Tenants and Products: Organization and Bank Setup](https://diameterpay.mintlify.app/concepts/tenants-and-products.md): Learn how Tenants represent your organization and how Products define your bank integrations, account types, and compliance rules in the Diameter platform.
- [End Users: Onboarding Individuals and Organizations](https://diameterpay.mintlify.app/concepts/end-users.md): End users are the individuals and organizations that use your financial services. Learn about their lifecycle, statuses, and required data.
- [Diameter Virtual Accounts: Retrieval and Balance Checks](https://diameterpay.mintlify.app/concepts/accounts.md): Virtual accounts are automatically created when an end user completes bank onboarding. Learn how to retrieve account details and check balances.
- [Payments: Wire Transfers and Internal Transactions](https://diameterpay.mintlify.app/concepts/payments.md): Diameter supports domestic wire, international wire, and internal transfers. Learn about payment types, statuses, and the full payment lifecycle.
- [Diameter Counterparties: Register and Manage Recipients](https://diameterpay.mintlify.app/concepts/counterparties.md): Counterparties represent the recipients of wire payments. Pre-registering them avoids compliance delays and speeds up payment processing.
- [How to Onboard an End User with Diameter](https://diameterpay.mintlify.app/guides/onboard-end-user.md): Step-by-step guide to creating individual or organization end users, tracking their onboarding status, and retrieving their virtual accounts.
- [How to Initiate Wire Payments with Diameter](https://diameterpay.mintlify.app/guides/initiate-payment.md): Learn how to initiate domestic wire, international wire, and internal transfers using the Diameter API, with idempotency and status tracking.
- [Create and Manage Payment Counterparties](https://diameterpay.mintlify.app/guides/manage-counterparties.md): Learn how to create, search, and manage counterparties for wire payments, including onboarding them to additional bank partners.
- [Set Up and Handle Diameter Webhooks](https://diameterpay.mintlify.app/guides/webhooks.md): Diameter sends real-time event notifications to your endpoint for payments, end users, accounts, and counterparties. Learn how to subscribe and verify.
- [Test Your Integration in the Diameter Sandbox](https://diameterpay.mintlify.app/guides/sandbox-testing.md): The Diameter sandbox lets you simulate inbound wires, test end-to-end payment flows, and verify webhook handlers without real money.
- [Diameter API Version History, Changelog, and Release Notes](https://diameterpay.mintlify.app/changelog.md): Track all Diameter API changes: new features, breaking changes, and deprecations across every version from the current release back to v0.5.0.
- [Diameter API Reference Overview](https://diameterpay.mintlify.app/api-reference/overview.md): Complete REST API reference for the Diameter banking platform. Base URLs, versioning, request format, pagination, and error handling.
- [Create an Individual End User](https://diameterpay.mintlify.app/api-reference/end-users/create-individual.md): POST /v1/end-users/individuals — Creates a new individual end user and initiates bank onboarding. Requires end-users.write scope.
- [Create an Organization End User](https://diameterpay.mintlify.app/api-reference/end-users/create-organization.md): POST /v1/end-users/organizations — Creates a new organization (business) end user and initiates bank onboarding. Requires end-users.write scope.
- [Get Individual End User by ID](https://diameterpay.mintlify.app/api-reference/end-users/get-individual.md): GET /v1/end-users/individuals/{id} — Retrieves a single individual end user by their UUID. Requires end-users:read scope.
- [Get Organization End User by ID](https://diameterpay.mintlify.app/api-reference/end-users/get-organization.md): GET /v1/end-users/organizations/{id} — Retrieves a single organization end user by UUID. Requires end-users:read scope.
- [Search Individual End Users](https://diameterpay.mintlify.app/api-reference/end-users/search-individuals.md): GET /v1/end-users/individuals — Search and filter individual end users with pagination. Requires end-users:read scope.
- [Search Organization End Users](https://diameterpay.mintlify.app/api-reference/end-users/search-organizations.md): GET /v1/end-users/organizations — Search and filter organization end users with pagination. Requires end-users:read scope.
- [Get Accounts for an Individual End User](https://diameterpay.mintlify.app/api-reference/end-users/get-individual-accounts.md): GET /v1/end-users/individuals/{id}/accounts — Returns all virtual accounts for an individual end user. Requires end-users:read scope.
- [Get Accounts for an Organization End User](https://diameterpay.mintlify.app/api-reference/end-users/get-organization-accounts.md): GET /v1/end-users/organizations/{id}/accounts — Returns all virtual accounts for an organization end user. Requires end-users:read scope.
- [Onboard Existing End User to Another Bank](https://diameterpay.mintlify.app/api-reference/end-users/onboard-existing.md): PATCH /v1/end-users/{id}/onboard — Starts onboarding an already-created end user with a new bank partner. Idempotent if already onboarded.
- [Get Account by ID](https://diameterpay.mintlify.app/api-reference/accounts/get-account.md): GET /v1/accounts/{id} — Retrieves a single virtual account by UUID, including account number, bank, currency, and wire instructions.
- [Get Account Balance](https://diameterpay.mintlify.app/api-reference/accounts/get-balance.md): GET /v1/accounts/{id}/balance — Returns the available balance and currency for a virtual account. Rate limited to 15 requests per second.
- [Search Accounts](https://diameterpay.mintlify.app/api-reference/accounts/search-accounts.md): GET /v1/accounts — Search virtual accounts with filters for account name, number, end user, or product. Returns paginated results.
- [Initiate an Outbound Domestic Wire Payment](https://diameterpay.mintlify.app/api-reference/payments/initiate-domestic-wire.md): POST /v1/payments/wire/domestic — Send an outbound domestic wire with ABA routing. Requires com.diameterpay.api/payments.write scope.
- [Initiate an Outbound International Wire Payment](https://diameterpay.mintlify.app/api-reference/payments/initiate-international-wire.md): POST /v1/payments/wire/international — Send an outbound international wire with BIC/SWIFT routing. Requires com.diameterpay.api/payments.write scope.
- [Initiate an Internal Transfer Between Accounts](https://diameterpay.mintlify.app/api-reference/payments/initiate-internal.md): POST /v1/payments/internal — Transfers funds between two accounts at the same bank partner. Requires com.diameterpay.api/payments.write scope.
- [Get Payment Details and Status by ID](https://diameterpay.mintlify.app/api-reference/payments/get-payment.md): GET /v1/payments/{id} — Retrieve full payment details and lifecycle status by Diameter payment UUID. Requires com.diameterpay.api/payments.read scope.
- [Search Payments by ID or End-to-End Reference](https://diameterpay.mintlify.app/api-reference/payments/search-payments.md): POST /v1/payments/search — Look up a payment by Diameter UUID or end-to-end reference ID. Requires com.diameterpay.api/payments.read scope.
- [Create a New Counterparty Payment Recipient](https://diameterpay.mintlify.app/api-reference/counter-parties/create.md): POST /v1/counter-parties — Register a new payment recipient for an end user. Pre-creating counterparties avoids delays at wire initiation time.
- [Get Counterparty Details and Status by ID](https://diameterpay.mintlify.app/api-reference/counter-parties/get.md): GET /v1/counter-parties/{id} — Retrieve a counterparty's details and bank onboarding status by UUID. Requires com.diameterpay.api/counter-parties.read scope.
- [Search and Filter Counterparties](https://diameterpay.mintlify.app/api-reference/counter-parties/search.md): GET /v1/counter-parties — Search and filter counterparties by end user, name, or type with pagination. Requires com.diameterpay.api/counter-parties.read scope.
- [Onboard a Counterparty to an Additional Bank Partner](https://diameterpay.mintlify.app/api-reference/counter-parties/onboard.md): PATCH /v1/counter-parties/{id}/onboard — Register an existing counterparty with an additional bank partner. Requires com.diameterpay.api/counter-parties.write scope.
- [Create a Webhook Subscription to Receive API Events](https://diameterpay.mintlify.app/api-reference/webhooks/create-subscription.md): POST /v1/webhook-subscriptions — Register an HTTPS endpoint to receive Diameter event notifications. Returns a one-time signing secret on creation.
- [List All Webhook Subscriptions Registered for Your Tenant](https://diameterpay.mintlify.app/api-reference/webhooks/list-subscriptions.md): GET /v1/webhook-subscriptions — Returns a paginated list of webhook subscriptions for your tenant. Filter by name, URL, or active status.
- [Get a Single Webhook Subscription by Its Unique ID](https://diameterpay.mintlify.app/api-reference/webhooks/get-subscription.md): GET /v1/webhook-subscriptions/{id} — Fetch the full configuration of a webhook subscription by ID. The signing secret is never returned after creation.
- [Update or Rotate the Secret on a Webhook Subscription](https://diameterpay.mintlify.app/api-reference/webhooks/update-subscription.md): PUT /v1/webhook-subscriptions/{id} — Updates the URL, name, event types, or active status of a webhook subscription. Requires webhooks.write scope.
- [Permanently Delete a Webhook Subscription by Its ID](https://diameterpay.mintlify.app/api-reference/webhooks/delete-subscription.md): DELETE /v1/webhook-subscriptions/{id} — Permanently removes a webhook subscription and stops all event delivery immediately. Cannot be undone.
- [Redeliver Webhook Events to a Specific Subscription](https://diameterpay.mintlify.app/api-reference/webhooks/redeliver-events.md): POST /v1/webhook-subscriptions/{id}/redeliver — Re-queues specific events or a time-window batch for redelivery. Supports up to 1,000 events per request.
- [Search Webhook Events by Type, Context, or Delivery Status](https://diameterpay.mintlify.app/api-reference/webhooks/search-events.md): GET /v1/webhooks/events/search — Query webhook events by type, context ID or type, and delivery status. Ideal for operational recovery after an outage.
- [Get a Single Webhook Event Record by Its Unique ID](https://diameterpay.mintlify.app/api-reference/webhooks/get-event.md): GET /v1/webhooks/events/{id} — Retrieves a single webhook event including its full JSON payload, context, and metadata. Requires webhooks.read scope.
- [Get All Delivery Attempt Records for a Webhook Event](https://diameterpay.mintlify.app/api-reference/webhooks/get-event-deliveries.md): GET /v1/webhooks/events/{id}/deliveries — Returns paginated delivery attempt records for a webhook event, including HTTP status codes and error details.
- [Bulk Mark Up to 100 Webhook Events as Manually Delivered](https://diameterpay.mintlify.app/api-reference/webhooks/bulk-mark-delivered.md): POST /v1/webhooks/events/bulk-mark-delivered — Marks up to 100 events as delivered to suppress further retry attempts after manual event processing.
- [List All Banking Products Configured for Your Tenant](https://diameterpay.mintlify.app/api-reference/products/list-products.md): GET /v1/products — Returns all products (bank integrations) provisioned for your tenant. Each product maps to one or more connected bank partners.
- [Get a Single Banking Product by Its Unique Product ID](https://diameterpay.mintlify.app/api-reference/products/get-product.md): GET /v1/products/{id} — Retrieves full configuration for a single product, including connected bank partners and reconciliation metadata.
- [Get the Aggregated Available Balance for a Product](https://diameterpay.mintlify.app/api-reference/products/get-product-balance.md): GET /v1/products/{id}/balance — Returns the aggregated available balance across all bank accounts associated with a product, in USD.
- [Get Your Tenant Record via the Current Access Token](https://diameterpay.mintlify.app/api-reference/tenants/get-tenant.md): GET /v1/tenants/self — Returns your tenant record, including provisioned products, allowed domains, and key identifiers. Requires tenants.read scope.
- [Simulate an Inbound Wire Payment in the Sandbox Env](https://diameterpay.mintlify.app/api-reference/simulation/simulate-payment.md): POST /v1/simulation/payments — Trigger a synthetic inbound wire in the sandbox environment to fund accounts and test your webhook integration end-to-end.
- [Check the Real-Time Operational Health of the Diameter API](https://diameterpay.mintlify.app/api-reference/diagnostics/health.md): GET /health — Returns the operational status of the Diameter API and its service dependencies. No authentication required. Use for uptime monitoring.


This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.