Limit order

Limit order is a trade request at a chosen price or better. A buy limit at 5.00 USDT only fills when price ≤ 5.00; a sell limit at 5.20 only at ≥ 5.20. If price never reaches the level, the order stays unfilled.

Price guaranteed, fill not

The mirror image of a market order: you know the price you would get, but not whether you’ll get a fill at all. If the market reverses before touching your level, the order sits idle.

That makes limit orders especially useful for:

• Large size where market-order slippage would eat into the trade.
• Entering at a target price (buy below spot, sell above).
• Take-profit and stop-loss logic.
• Market making (post-and-earn-the-spread).

Limit orders on TON DEXs

Pure AMMs cannot host limit orders directly: the pool prices deterministically off reserves, with no “book of orders below spot”.

The implementation pattern:

1. The user signs an off-chain message: “buy Δx at price ≤ P”.
2. The message lands with a keeper bot or in a dedicated order-book contract.
3. When the AMM pool’s price hits P, the keeper executes — runs a regular swap on behalf of the user and pockets a small share.

On TON, limit orders are offered by STON.fi (native module) and through certain DeDust front-ends. Storm Trade supports limit orders on perpetuals.

Maker vs taker

On order-book exchanges a limit order is a maker trade (adding liquidity to the book); a market order is a taker (removing it). Many CEXes set lower or even negative maker fees (rebates) to attract passive traders.

In an AMM world the line is blurred, but a limit order is conceptually closer to the maker role: willing to wait.

Pitfalls on DEXs

• Keeper fee. The bot that fires the order skims 0.1–0.3% on top.
• Expiry. Most implementations are not eternal; orders live for hours to weeks.
• Failure under stress. If price spikes through your level and reverses immediately, the keeper may miss it.

Limit orders are a must-have for size and strategy; market orders are for urgency and small ticks.