> ## Documentation Index
> Fetch the complete documentation index at: https://docs.ostium.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Opening a Trade

> Walkthrough for opening your first position on Ostium, with fee math and a worked example.

To open a trade on Ostium, select a market, choose long or short, set leverage (1x–200x), deposit USDC collateral, optionally configure take-profit and stop-loss, and submit your order for onchain settlement in seconds.

***

## Step-by-Step

<Steps>
  <Step title="Choose Your Market">
    Select from 75 markets across 6 asset classes: Stocks, ETFs, Commodities, Indices, Forex, and Crypto, all settled in USDC.

    * **Stocks**: AAPL, TSLA, NVDA, MSFT, and 29 more (33 total)
    * **ETFs**: HYG, KR2550, TLT, UNG, URA, XLE (6 total)
    * **Commodities**: XAU/USD (gold), XAG/USD (silver), WTI/USD (crude oil), and 4 more
    * **Indices**: US500/USD, US100/USD, US30/USD, GER40/EUR, and 3 more
    * **Forex**: EUR/USD, GBP/USD, USD/JPY, and 6 more (9 total)
    * **Crypto**: BTC/USD, ETH/USD, SOL/USD, and 6 more (9 total)

    Each pair has a maximum leverage cap and specific fee rate. See [Markets](/traders/reference/markets) for the full list.
  </Step>

  <Step title="Select Your Side">
    Choose **Long** (profit if price rises) or **Short** (profit if price falls). Both sides use the same leverage ranges and fee structures. All collateral and PnL are denominated in USDC.
  </Step>

  <Step title="Set Your Leverage">
    Leverage multiplies your position size: **<Tooltip tip="Total position value. Equals collateral × leverage.">Notional</Tooltip> = <Tooltip tip="USDC deposited to back a leveraged position. Determines position size and liquidation threshold.">Collateral</Tooltip> × Leverage**.

    * **Range**: 1x to 200x, depending on the pair
    * **Lower-volatility pairs** (e.g., EUR/USD): higher caps (up to 200x)
    * **Higher-volatility pairs** (e.g., certain ETFs): lower caps (as low as 50x)
    * **<Tooltip tip="Automatic position close when collateral falls below the maintenance threshold.">Liquidation</Tooltip> price**: Moves closer to entry as leverage increases. See [Liquidation](/traders/trading/liquidation) for thresholds.

    **Example**: 100 USDC collateral at 20x leverage = 2,000 USDC notional position.
  </Step>

  <Step title="Enter Collateral">
    Deposit USDC (Arbitrum native or bridged). This is your margin. All position sizing, fees, and PnL derive from it.

    * **Minimum collateral**: Pair-specific (typically \$10–\$100 USDC)
    * **Effective collateral**: Deposited amount minus opening fee minus oracle fee
    * **Position size**: Effective collateral × leverage
  </Step>

  <Step title="Set Take-Profit and Stop-Loss (Optional)">
    **Take-Profit (TP):**

    * Automatically closes your position at a target price
    * For longs, TP must be above current price; for shorts, below
    * Maximum TP: 900% above entry (i.e., entry price × 10). If you don't set one, the system applies this cap automatically.

    **Stop-Loss (SL):**

    * Automatically closes your position if price moves against you past this level
    * Must be set between current price and liquidation price
    * Free to set and adjust. Automated SL execution incurs no oracle fee.

    Leave both blank to manage manually from the Positions panel.
  </Step>

  <Step title="Choose Your Order Type">
    * **Market**: Executes immediately at the current ask (long) or bid (short) price.
    * **Limit**: Executes only when price reaches your target. Canceling a pending limit order costs \$0.10.
    * **Stop**: Triggers when price crosses a level, then executes as a market order.

    See [Order Types](/traders/trading/order-types) for detailed mechanics and examples.
  </Step>

  <Step title="Confirm and Submit">
    Review your order summary: pair, side, leverage, collateral, effective margin, notional size, TP/SL prices, estimated opening fee, oracle fee, and liquidation price.

    Click **Submit**. The keeper network fetches the current oracle price, deducts fees from your collateral, and opens the position onchain. This typically takes 1–2 seconds.
  </Step>

  <Step title="Monitor Your Position">
    Once open, your trade appears in the **Positions** panel with live PnL, mark price, liquidation price, and margin ratio. From there you can update TP/SL, add or remove collateral, or close manually at any time. See [Managing Positions](/traders/trading/managing-positions) for details.
  </Step>
</Steps>

***

## What It Costs to Open

Two fees are deducted from your collateral at open: the **opening fee** and the **oracle fee**.

### Opening Fee

The opening fee is a one-time charge calculated on your **notional position size** (collateral × leverage) and deducted from collateral.

| Asset Class | Fee                                                                  |
| ----------- | -------------------------------------------------------------------- |
| Stocks      | 6 <Tooltip tip="1 basis point = 0.01%. 6 bps = 0.06%.">bps</Tooltip> |
| ETFs        | 5 bps                                                                |
| Commodities | 3–5 bps (gold 3 bps, others 5 bps)                                   |
| Indices     | 3 bps                                                                |
| Forex       | 3 bps (5 bps for USD/MXN, USD/KRW)                                   |
| Crypto      | 10 bps                                                               |

### Oracle Fee

A flat \$0.10 USDC per price request. Charged at open. Refunded on a successful full close. Not charged on automated TP/SL executions.

<Note>
  If a market open fails due to slippage, your collateral is returned but the \$0.10 oracle fee is consumed.
</Note>

### Effective Collateral

```
Effective Collateral = Deposited Collateral − Opening Fee − Oracle Fee
Position Notional = Effective Collateral × Leverage
```

### Worked Example

**Scenario**: Open a 10x long on ETH/USD with 1,000 USDC collateral.

1. Deposit: **1,000 USDC**
2. Notional position: 1,000 × 10 = **10,000 USDC**
3. Opening fee: 10,000 × 10 bps = **10 USDC** (calculated on notional, deducted from collateral)
4. Oracle fee: **\$0.10**
5. Effective collateral: 1,000 − 10 − 0.10 = **989.90 USDC**
6. Final notional: 989.90 × 10 = **9,899 USDC**

If ETH/USD moves \~10% against you, your loss approaches your effective collateral and the position is liquidated.

For the full fee schedule, holding costs (rollover and funding), and liquidation details, see [Fees](/traders/reference/fees).

***

## FAQ

<Accordion title="What happens if I don't set a stop-loss?">
  Your position stays open until you manually close it or price reaches your liquidation threshold. Without a stop-loss, large moves against you can wipe out your collateral before you have time to react.
</Accordion>

<Accordion title="Can I change my leverage after opening?">
  Not directly. Leverage is set at open. However, you can adjust your effective leverage by adding collateral (which lowers leverage) or removing collateral (which raises it). See [Managing Positions](/traders/trading/managing-positions).
</Accordion>

<Accordion title="Why was my effective collateral less than what I deposited?">
  The opening fee and oracle fee are deducted from collateral at open. See the **Worked Example** above for the full calculation.
</Accordion>

***

<Note>
  **Building this programmatically?** The Builder SDK exposes [`openTrade()`](/developer/reference/open-trade) for market, limit, and stop orders. See [Trader Quickstart](/developer/traders/approvals-and-first-trade) for a working example.
</Note>

## What to Read Next

* **[Managing Positions](/traders/trading/managing-positions)** — Adjust TP/SL, add collateral, and track PnL.
* **[Fees](/traders/reference/fees)** — Complete fee breakdown: opening, rollover, funding, liquidation.
* **[Order Types](/traders/trading/order-types)** — Market, limit, and stop orders with examples.