# Create a branch

**POST** `/v1/projects/{projectId}/branches`

⚠️ Experimental endpoint: this API is in active development and may change at any time without notice. ⚠️

Creates a Branch under the specified Project. The first Branch in a Project is always created with isDefault=true and role=production regardless of the body value. Later Branches are created with role=preview. Setting isDefault=true while another Branch already holds the default atomically swaps the default flag only.

Base URL: `https://api.prisma.io`

Tags: `[Experimental]`

## Authorization

Any ONE of the following options authorizes this operation; every scheme listed within an option is required together.

| Option | Scheme | Type | Sent as | Scopes |
| --- | --- | --- | --- | --- |
| Option 1 | `OAuth2` | `oauth2` | `Authorization: Bearer <access token>` | `offline_access`, `workspace:admin` |
| Option 2 | `Bearer` | `http` | `Authorization: Bearer <token>` (JWT) | — |

### OAuth 2.0 flows

- **OAuth2 · authorizationCode**
  - Authorization URL: `https://auth.prisma.io/authorize`
  - Token URL: `https://auth.prisma.io/token`
  - Refresh URL: `https://auth.prisma.io/token`
  - Scope `offline_access` — Offline access
  - Scope `workspace:admin` — Full access to workspace resources

## Path parameters

| Name | Type | Required | Description |
| --- | --- | --- | --- |
| `projectId` | `string` | Yes | — |

## Request body

Optional. Media type: `application/json`

### Example request body

```json
{
  "gitName": "string",
  "isDefault": true
}
```

## Responses

| Status | Description | Media type |
| --- | --- | --- |
| `201` | Created the Branch. | `application/json` |
| `401` | Missing or invalid authorization token. | `application/json` |
| `404` | Project not found. | `application/json` |
| `409` | A live Branch with the same gitName already exists. | `application/json` |
| `422` | Invalid gitName. | `application/json` |

### Example response: 201 — Created the Branch.

```json
{
  "data": {
    "createdAt": "2026-06-09T00:00:00Z",
    "gitName": "string",
    "id": "string",
    "isDefault": true,
    "project": {
      "id": "string",
      "name": "string",
      "url": "https://example.com"
    },
    "role": "preview",
    "type": "branch",
    "updatedAt": "2026-06-09T00:00:00Z",
    "url": "https://example.com"
  }
}
```

### Example response: 401 — Missing or invalid authorization token.

```json
{
  "error": {
    "code": "string",
    "hint": "string",
    "message": "string"
  }
}
```

### Example response: 404 — Project not found.

```json
{
  "error": {
    "code": "string",
    "hint": "string",
    "message": "string"
  }
}
```

### Example response: 409 — A live Branch with the same gitName already exists.

```json
{
  "error": {
    "code": "string",
    "hint": "string",
    "message": "string"
  }
}
```

### Example response: 422 — Invalid gitName.

```json
{
  "error": {
    "code": "string",
    "hint": "string",
    "message": "string"
  }
}
```

## Related pages

- [[Experimental]](./tags/experimental.md)
- [Acquire Alchemy deploy lease](./postv1projectsbyprojectidbranchesbybranchidalchemy-statelease.md)
- [Agents](./tags/agents.md)
- [Alchemy state store version](./getv1projectsbyprojectidbranchesbybranchidalchemy-stateversion.md)
- [Buckets](./tags/buckets.md)
- [Connections](./tags/connections.md)
- [Create a custom domain](./postv1appsbyappiddomains.md)
- [Create a custom domain](./postv1servicesbyserviceiddomains.md)
- [Create a workspace](./postv1workspaces.md)
- [Create an environment variable](./postv1environment-variables.md)

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