A mortgage that can be transfered with no change in terms. If an assumable mortgage is transferred, the buyer assumes all responsibility for repayment. The original lender must agree to the transfer of an assumable mortgage. The seller should receive a written release from the original lender stating that he/she has no responsibility for further payments. The buyer may have to meet certain standards to qualify and may be charged an assumption fee. Assumable mortgages can make a property more desirable if interest rates have risen, because the new buyer's payments are at the original rate. By definition, assumable mortgages cannot have a due-on-sale clause.