Premium is a term used in financial markets which describes when a security is trading above its normal price.  An asset or fund could be described as being at a premium when its market price is above its face value.  In the capital markets, premium is the amount by which a bond sells above par.  In foreign exchange premium is the margin by which the forward rate is higher than the spot rate.  In commodity markets premium is the additional price paid by a consumer when the delivered commodity is of better quality than that specified in the original contract (which would not apply at IB since IB does have the facilities to accommodate physical delivery and therefore does not allow clients to hold positions in futures contracts which result in physical delivery, into the date which physical delivery could occur).