Market, limit and stop orders: how and where an order fills

Three kinds of order

• Market order — buy or sell now, at the best prices waiting in the order book. It fills at once, but the price is whatever the book offers; a large order can eat through several levels (slippage).
• Limit order — buy at this price or lower, or sell at this price or higher. It waits in the book until someone trades with it — or never fills.
• Stop order — waits unseen until a trade prints at its trigger price, then sends a market order (on Binance spot, a STOP_LOSS order; a STOP_LOSS_LIMIT sends a limit order instead). A stop-loss under a long position is a sell stop.

Order types — 14:00–15:00 UTC on 2 October 2026 on Binance's BTC/USDT. A market buy at 14:00 paid about 86,565. A buy limit at 85,700 filled at 14:34, when price traded down to 85,692. A buy limit at exactly the hour's low, 85,394.44, may or may not have filled; one at 85,300 was never reached. In the minute 14:34, a sell stop at 85,900 triggered at 14:34:17.7 and trades printed as low as 85,847.76 within 2 seconds; a stop at 85,800 triggered at 14:34:28.0, and trades printed as low as 85,731.69 within 2 seconds.

Touched is not filled

A candle's wick shows the lowest trade, not who traded there. Orders at one price fill in the order they were placed: if price only touches your limit and turns, the orders ahead of yours may have used up all the selling. Only when price trades through your limit is a resting order certain to have filled.

Why orders gather at round numbers

Traders place orders at round prices, and it shows on the chart: from June to October 2026, BTC's hourly highs and lows landed exactly on a round $500 price 71 times — about 16 times as often as on other whole-dollar prices. A study of a bank's currency orders, published by the Federal Reserve Bank of New York, found the same clustering at round numbers.

Check yourself · 1 of 3You place a buy limit at 85,000 while BTC trades at 86,000. When does it fill?

AAt once, at 86,000BOnly if price trades down to 85,000 or lowerCNever — limits only sell

Show the answer

A buy limit waits below the price and fills only at its price or better.

Check yourself · 2 of 3The hour's low is exactly your buy limit's price. Did it fill?

AYes, alwaysBNo, neverCMaybe — orders at that price fill in the order they were placed

Show the answer

Only a trade through the price makes a resting limit certain to have filled.

Check yourself · 3 of 3Your sell stop at 85,900 is triggered in a fast fall. What price do you get?

AExactly 85,900BWhatever buyers pay right after — possibly below 85,900CThe day's close

Show the answer

A stop sends a market order once triggered; it fills at the next prices available.

Takeaways

1. Market: fills now, at the book's prices. Limit: at your price or better, maybe never. Stop: a market order once its price trades.
2. A wick touching your limit is not proof of a fill; a trade through it is.
3. A stop limits a loss to roughly its price — below it in a fast market.
4. Orders cluster at round numbers, and highs and lows land on them far more often than chance.

Open BTC in the terminal — watch the order book and the trades as they happen

Further reading

• Order types: LIMIT, MARKET, STOP_LOSS, STOP_LOSS_LIMIT — Binance Spot API docs ↗
• Osler, Currency Orders and Exchange-Rate Dynamics (orders cluster at round numbers) — Federal Reserve Bank of New York Staff Report 125 ↗
• Aggregate trades and klines, where this lesson's data comes from — Binance Spot API docs ↗