Can a limit order at 100 still take liquidity? Understand the Post Only constraint
You chose a limit order, so why did it still take liquidity? On Binance Spot, a limit order specifies the acceptable execution price; whether a trade is Maker or Taker depends on whether it actively consumes an existing order. A regular limit order that matches immediately may be charged the Taker fee. You can't determine this from the order name alone.
Consider a purely hypothetical order book: the best ask is 100 USDT, with 10 units posted, and nothing changes before matching. The order complies with the trading rules. A regular limit buy order for 1 unit at a price of 100 will execute at 100, consuming the seller's resting order. Even if you set the buy limit price to 101, that 1 unit can still execute at 100; the limit price is simply the highest price you are willing to pay.
Under the same conditions, submit a LIMIT_MAKER order—also known as Post Only—through the Binance Spot API. A buy order at either price will be rejected because it would immediately take liquidity; it won't execute first and then become a resting order. This constraint means the order is accepted only if it first enters the order book and then executes as a Maker. If the price won't immediately match an existing sell order, the order may be posted normally, but being posted does not guarantee execution.
Fees depend on the actual execution role and the rates applicable to your account. A regular GTC limit order can first take some liquidity, with any remaining quantity resting on the book and later executing as a Maker. Maker fees are not always lower than Taker fees; check the trading pair, account tier, promotions, and actual fees charged. Even when a fee discount applies, consider it alongside price changes while you wait: paying less in fees does not mean the total transaction cost will be lower, nor does it mean the price won't move against you after execution.
A rejection means you did not obtain the desired quantity this time. If you don't want to risk rejection or wait, reconsider your execution constraints rather than treating Post Only as a cost-saving switch that guarantees execution. Liquidity and prices can change while you wait; if you decide to cancel, check the cancellation result and the quantity already executed.
An order-book snapshot does not guarantee the execution price later on, and the example holds only under the stated conditions; actual buy orders remain subject to their limit prices. This article explains execution costs only. It does not predict price movements or guarantee returns.
https://developers.binance.com/docs/binance-spot-api-docs/rest-api/trading-endpoints
#SpotTrading #TradingCosts
You chose a limit order, so why did it still take liquidity? On Binance Spot, a limit order specifies the acceptable execution price; whether a trade is Maker or Taker depends on whether it actively consumes an existing order. A regular limit order that matches immediately may be charged the Taker fee. You can't determine this from the order name alone.
Consider a purely hypothetical order book: the best ask is 100 USDT, with 10 units posted, and nothing changes before matching. The order complies with the trading rules. A regular limit buy order for 1 unit at a price of 100 will execute at 100, consuming the seller's resting order. Even if you set the buy limit price to 101, that 1 unit can still execute at 100; the limit price is simply the highest price you are willing to pay.
Under the same conditions, submit a LIMIT_MAKER order—also known as Post Only—through the Binance Spot API. A buy order at either price will be rejected because it would immediately take liquidity; it won't execute first and then become a resting order. This constraint means the order is accepted only if it first enters the order book and then executes as a Maker. If the price won't immediately match an existing sell order, the order may be posted normally, but being posted does not guarantee execution.
Fees depend on the actual execution role and the rates applicable to your account. A regular GTC limit order can first take some liquidity, with any remaining quantity resting on the book and later executing as a Maker. Maker fees are not always lower than Taker fees; check the trading pair, account tier, promotions, and actual fees charged. Even when a fee discount applies, consider it alongside price changes while you wait: paying less in fees does not mean the total transaction cost will be lower, nor does it mean the price won't move against you after execution.
A rejection means you did not obtain the desired quantity this time. If you don't want to risk rejection or wait, reconsider your execution constraints rather than treating Post Only as a cost-saving switch that guarantees execution. Liquidity and prices can change while you wait; if you decide to cancel, check the cancellation result and the quantity already executed.
An order-book snapshot does not guarantee the execution price later on, and the example holds only under the stated conditions; actual buy orders remain subject to their limit prices. This article explains execution costs only. It does not predict price movements or guarantee returns.
https://developers.binance.com/docs/binance-spot-api-docs/rest-api/trading-endpoints
#SpotTrading #TradingCosts