# Double Position

> Places a market order matching the position's symbol, side, and remaining open quantity. When the order fills, the resulting deal is merged into the existing position (VWAP recalculation + quantity increase).

Source: /trader/api/trading/double-position

## `POST /accounts/{account_id}/positions/{position_id}/double`

**Double Position**

Places a market order matching the position's symbol, side, and remaining open quantity. When the order fills, the resulting deal is merged into the existing position (VWAP recalculation + quantity increase).

Tags: `Trading`

#### Path parameters

- `account_id` (string) (required) — The account ID where the position to double belongs
- `position_id` (string) (required) — Position ID to double


### Responses

#### `201` — Position double order created successfully

**Content-Type:** `application/json`

- `order_id` (string) (required) — The created doubling market order identifier

#### `400` — Bad request (missing or invalid fields)

**Content-Type:** `application/json`

- `error` (object) (required)
  - `type` (string) (required) — Error type code
  - `message` (string) (required) — Human-readable error message
  - `field` (string) — Field name if error is field-specific

#### `401` — Unauthorized (invalid or missing JWT token)

**Content-Type:** `application/json`



#### `403` — Forbidden (position access denied)

**Content-Type:** `application/json`



#### `404` — Position not found

**Content-Type:** `application/json`



#### `422` — Unprocessable entity (business rule violation, e.g. position not open)

**Content-Type:** `application/json`



#### `500` — Internal server error

**Content-Type:** `application/json`