In the Order section of the Exchange view you will find two different order types - Limit and Market Order.
Limit order
A limit order is not meant to be executed instantly but is used to place an order in the order book that executes at your specified limit price (or a better price).
For example, if the price for BTC/USDT is currently at 80,000 USDT and you place a limit buy order with a limit price of 75,000 USDT, your order will execute at 75,000 USDT as soon as there are matching sell orders at this price.
However, if the price for BTC/USDT is currently at 80,000 USDT and you place a limit buy order with a limit price of 85,000 USDT, it will initially act as a market order, buying up (at better prices) until it reaches your specified limit price (incurring a taker fee). If the order amount is larger than what is available in the order book at that moment, the remaining amount will stay open as a limit buy order (and will incur a maker fee).
Note: When placing a limit order, please understand that if there are no or not enough matching sell orders, your order may not execute or may only execute partially.
If you want to place an order that does not get executed immediately, to buy at a lower price than the market price or sell at a higher price than the market price, you might want to use this order type.
Advanced limit orders (Time in force)
Good ‘til Cancelled (GTC) - This is the default order type for limit orders. The order stays active until it’s either executed or cancelled.
Immediate or Cancel (IOC) - The limit order is placed and if it is not immediately filled(fully, or as fully as possible), it will automatically be cancelled and removed from the order book. Non-executed parts of an IOC order are deleted without entry in the order book.
Fill or Kill (FOK) - Limit order which has to be executed and fully or not at all. If immediate and full execution is not possible, the FOK order is deleted without entry in the order book.
Market Orders and Slippage Protection
A Market Order is an instruction to buy or sell a certain amount of assets at the best price available in our order books.
A Market Order should be treated with caution, as there is a risk of "slippage": In case the order book is not liquid enough, the price against which the asset is bought or sold may be substantially less favourable than the most recent trade price.
We have implemented slippage protection for your benefit: The default level of slippage protection set by us is 25%, but you may adjust it from 10% (least slippage risk) to 90% (highest slippage risk).
As a consequence, if you attempt to execute a market order, this will create a Limit Order with type ‘IOC - Immediate or Cancel’ at a price that is, e.g. 25% different to the current best ask (for purchases)/bid (for sales) price on the One Trading Platform.
For example at 25%:
Current best ask price of the asset = €100
Market Buy order would enter a Limit IOC buy for a price of €125
Current best bid price of the asset = €100
Market Sell order would enter a Limit IOC for a price of €75
As a Limit Order going into the order book, it is usually likely that the order will fill at a more favourable price than the given 25%. Please also be aware that your Market Order may not execute fully (due to the conversion into an Immediate or Cancel Limit Order), and that your order and transaction history will only reflect such Limit Order. You can adjust your slippage percentage protection in Profile/Settings.