In ICE FX, all orders are executed using the Market method, that is, at a price, which is the current one at the moment in the market.
An order can’t be executed instantly because it takes time to be opened by a counterparty. In this regard, at the moment of a sharp change in quotes, an order may slip, i.e., executed at a price different from the requested one.
On ICE FX demo accounts, orders are executed using the Instant method. Demo accounts receive quotes from the same liquidity aggregator as real ones. However, transactions are not sent to the counterparty. Therefore, it is practically impossible for orders to slip on demo accounts.
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