Mortgage Stamp Duty (focusing on NSW) In NSW there is duty payable on mortgages. Most people think it is abolished, but it is still around unfortunately. However there is an exception for someone who is a natural person, and is purchasing land (a property) So it won't apply to most people. There are 2 main reasons where people get caught with having to pay duty: A company is the mortgagor which usually means the company is the borrower, and/or where a person is borrowing without the purchase of a property. This can happen when setting up a line of credit (LOC) or releasing equity by borrowing to park money in an offset account (avoid this if possible) or pay back into the loan. Stamp duty is administered by the OSR but usually collected by the banks when doing the loan. Often they miss the collection of the duty on the LOC set up, but that doesn’t mean the person borrowing is not liable. Tax is self assessment so you should offer to pay the tax to the OSR where they have missed it. But where a person has paid stamp duty on a LOC type loan and the funds are later used to acquire a property the duty in this case can be refunded by the OSR if an application is made with proof.