---
title: "Create counterparty"
method: POST
path: "/v1/counterparties"
tags: ["Counterparties"]
---

# Create counterparty

`POST /v1/counterparties`

Creates a counterparty. If externalId is provided, it must be unique within the organization.

## Headers

- `x-project-id` string — Selects the active project for this request. Required for session/dashboard callers. Ignored when authenticating with an API key, whose scope is fixed to the key's project.

## Request body

- object — Create counterparty request body.
  - `externalId` string — Caller-supplied opaque identifier for cross-system reference. Do not place personal data in this indexed field.
  - `entityType` 'individual' | 'business', required — Counterparty entity type.
  - `displayName` string, required — Human-readable, searchable display name. Keep it minimal because this indexed field is not application-encrypted.

## Response `201`

Counterparty created

- object — Standard success response envelope.
  - `data` object, required — Counterparty response payload.
    - `counterparty` object, required — Counterparty record.
      - `id` string, required — Counterparty identifier.
      - `organizationId` string, required — Organization identifier.
      - `projectId` string, nullable, required — Project scope when the counterparty is project-scoped.
      - `externalId` string, nullable, required — Caller-supplied opaque identifier for cross-system reference. Do not place personal data in this indexed field.
      - `entityType` 'individual' | 'business', required — Counterparty entity type.
      - `displayName` string, required — Human-readable, searchable display name. Keep it minimal because this indexed field is not application-encrypted.
      - `status` 'active' | 'archived', required — Counterparty status.
      - `createdBy` string, nullable, required — User who created the counterparty. Null when created via API key.
      - `createdAt` string, date-time, required — Creation timestamp.
      - `updatedAt` string, date-time, required — Last update timestamp.
  - `meta` object, required — Response metadata.
    - `requestId` string, required — Request identifier for tracing.
    - `timestamp` string, date-time, required — ISO 8601 timestamp.

## Other responses

- `400` — Error
- `401` — Error
- `403` — Error
- `409` — Error
- `500` — Error

---

[API](https://skmtc.dev/solana/apis/solana-developer-platform-api.md) · [All operations](https://skmtc.dev/solana/apis/solana-developer-platform-api/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/solana/solana-developer-platform-api/revisions/13f3098243d6/schema)