Slippage is a key element of the financial markets irrespective of you are trading Stocks, Futures, Commodities or Forex, you will be subject to slippage.

When you place a market order, you are requesting your order be filled at the current market prices; however, if the market has moved between the time you place your order and the time it has been filled, your order may be filled at a different price. Slippage can increase when markets become volatile, such as over new releases.