Edit, sign, and share assumption agreement online. No need to install software, just go to DocHub, and sign up instantly and for free.In real estate transactions, an assumption agreement allows a third party to "assume" or take over the loan of the property's seller. If the current mortgage is assumable, both parties must complete a loan assumption agreement. â–¡ Purchase and sale agreement (if applicable). â–¡ Draft assignment and assumption agreement (if applicable).