You do not have to reduce your original home loan principle. As the title indicates, an interest only mortgage or home loan means your repayments only have to cover the interest portion of the loan. After all it is only the interest you ... The mortgage loan itself is made by a bank, a savings and loan association, a mortgage company, a credit union, or any other lender. For it to become an FHA mortgage loan, the lender would have to be approved by the Federal Housing Administration.