I mostly trade futures. I know that you can buy at Ask Price OR sell at Bid Price to open a trade. I'm confused about the price that trades are closed at. I thought that if I was long and had a sell limit order to close the trade that it would execute at the Bid price, but it appears to execute at the Last Price instead. Is the above how it is supposed to work? IOW, closing orders with limit orders executes on Last Price and not on Ask/Bid Prices. Or does a closing order execute on Average Price?