Lenders often require mortgage insurance for loans where the downpayment is less than 20% of the sales price. You may be billed monthly, annually, by an initial lump sum, or some combination of these practices for your mortgage insurance premium. Ask your lender if mortgage insurance is required and how much it will cost. Mortgage insurance should not be confused with mortgage life, credit life or disability insurance, which are designed to pay off a mortgage in the event of the borrower's death or disability.