Assumption of SBA Loan. Assumption of Loan Requirement Letter for disaster loan servicing action request packages.About this document and download. What Is Required to Assume an SBA 504 Loan? The SBA 504 Loan is a long-term, fixed rate loan utilized to purchase fixed assets which promotes business growth and job. SBA Loan Forms: Complete all SBA-required forms included in the application package. SBA loans, including the SBA 7(a) loan, are fully assumable with SBA approval. Another option to sell a business with an SBA loan is for the buyer to assume the loan. SBA loans are fully assumable with SBA approval. Our office provides help with SBA services including funding programs, counseling, federal contracting certifications, and disaster recovery.