Can An SBA 504 Loan Be Assumed? Many types of loans are not assumable.Are SBA 7(a) Loans Assumable? Fortunately for borrowers, SBA loans, including the SBA 7(a) loan , are fully assumable with SBA approval. Assumption of Loan Requirement Letter. Assumption of Loan Requirement Letter for disaster loan servicing action request packages. The SBA offers information on small business loans, grants, bonds and other financial assistance. : Fill out the lender's application form detailing the business and loan request. An assumable mortgage involves one borrower taking over, or assuming, another borrower's existing home loan. Find out how it works.