Private Mortgage Insurance ALL0-9ABCDEFGHIJKLMNOPQRSTUVWXYZ Mortgage insurance provided by a private mortgage insurance company to protect lenders against loss if a borrower defaults. Most lenders generally require MI for a loan with a loan-to-value (LTV) percentage in excess of 80 percent. Related Articles: Glossary: Insured MortgageDC Open Doors and the Maryland Mortgage ProgramEssential Checklist for First-Time HomebuyersDoctors Mortgage Program