Is it possible to short bonds (not bond futures) in your account and have the cash available to withdraw and use? I got thinking about this while trying to figure out how, exactly, a mortgate bank can tie the loan rate to the 30 year t-bond.. maybe it is just correlated.. The way I figure it, giving a loan is like buying a bond: pay out lump sum, collect interest payments. So the mortgage bank would need to short a bond to balance out the bond they "bought" from the borrower, and be neutral. Then they they just rake in the spread, which is the difference between interest rates. Is this remotely close to how it works? Is it possible for an individual to short a bond and get access to the cash? And possibly even create their own mortgage?