| $150,000–350,000 | LUNA BUILDS STL | SAINT LOUIS, MO | Lindell Bank & Trust Company |
| $150,000–350,000 | LUTHERAN ASSOC | SAINT LOUIS, MO | Midwest BankCentre |
| $1–2 million | LUTHERAN FAMILY AND CHILDREN'S SERVICES OF MISSOURI | SAINT LOUIS, MO | The Bank of Missouri |
| $150,000–350,000 | LUTHERAN GERIATRIC CARE, INC. | SAINT LOUIS, MO | BMO Bank National Association |
| $1–2 million | LUTHERAN HIGH SCHOOL ASSOCIATION OF ST. LOUIS | SAINT LOUIS, MO | Southern Bank |
| $150,000–350,000 | LUX ROW DISTILLERS, LLC | SAINT LOUIS, MO | BMO Bank National Association |
| $2–5 million | LUXCO INC. | SAINT LOUIS, MO | BMO Bank National Association |
| $150,000–350,000 | LUZCO TECHNOLOGIES, LLC | SAINT LOUIS, MO | Enterprise Bank & Trust |
| $150,000–350,000 | LYNN'S ELECTRIC, LLC | SAINT LOUIS, MO | Triad Bank |
| $1–2 million | LYON SHEET METAL, INC. | SAINT LOUIS, MO | Midwest BankCentre |
| $150,000–350,000 | M & L FROZEN FOODS, INC. | SAINT LOUIS, MO | Commerce Bank |
| $150,000–350,000 | M & P LANDSCAPING | SAINT LOUIS, MO | The Bank of Houston |
| $350,000–1 million | M FERNANDEZ DDS, E BROWN DDS, J OSDIECK DMD, K JOBE DDS, LLC | SAINT LOUIS, MO | Carrollton Bank |
| $150,000–350,000 | M-CO, LLC | SAINT LOUIS, MO | Busey Bank |
| $150,000–350,000 | M3 ENGINEERING GROUP PC | SAINT LOUIS, MO | PNC Bank, National Association |
| $150,000–350,000 | MABLAY CONSTRUCTION LLC | SAINT LOUIS, MO | U.S. Bank, National Association |
| $350,000–1 million | MACKEY MITCHELL ARCHITECTS, P.C. | SAINT LOUIS, MO | Commerce Bank |
| $150,000–350,000 | MACLAN INDUSTRIES INC | SAINT LOUIS, MO | Carrollton Bank |
| $150,000–350,000 | MAGDALA FOUNDATION | SAINT LOUIS, MO | Bank of America, National Association |
| $150,000–350,000 | MAGNETIZE, LLC | SAINT LOUIS, MO | Bank of Franklin County |
| $350,000–1 million | MAHER & COMPANY PC | SAINT LOUIS, MO | Carrollton Bank |
| $350,000–1 million | MAI LEE RESTAURANT LLC | SAINT LOUIS, MO | St. Louis Bank |
| $350,000–1 million | MALISKO ENGINEERING INC. | SAINT LOUIS, MO | St. Louis Bank |
| $150,000–350,000 | MANAGEMENT RECRUITERS OF WESTPORT INC | SAINT LOUIS, MO | Commerce Bank |
| $150,000–350,000 | MANCHESTER HOLDINGS, LLC | SAINT LOUIS, MO | Triad Bank |
| $150,000–350,000 | MANUFACTURER'S SOLUTION ALLIANCE, LLC | SAINT LOUIS, MO | Triad Bank |
| $150,000–350,000 | MARIAN MIDDLE SCHOOL | SAINT LOUIS, MO | Great Southern Bank |
| $2–5 million | MARIANIST PROVINCE OF THE UNITED STATES | SAINT LOUIS, MO | Fifth Third Bank |
| $150,000–350,000 | MARINO ENGINEERING ASSOCIATES, INC. | SAINT LOUIS, MO | Busey Bank |
| $150,000–350,000 | MARK A SCHEPERLE INC | SAINT LOUIS, MO | Busey Bank |
| $150,000–350,000 | MARKEL ENTERTAINMENT, LLC. | SAINT LOUIS, MO | Royal Banks of Missouri |
| $350,000–1 million | MARKETPLACE INNOVATIONS LLC | SAINT LOUIS, MO | PNC Bank, National Association |
| $150,000–350,000 | MARKWORT SPORTING GOODS COMPANY | SAINT LOUIS, MO | First Bank |
| $150,000–350,000 | MARLER SURVEYING COMPANY, INC. | SAINT LOUIS, MO | Triad Bank |
| $1–2 million | MARTHA'S HANDS, LLC | SAINT LOUIS, MO | The Central Trust Bank |
| $150,000–350,000 | MARTIN ELECTRICAL SALES INC | SAINT LOUIS, MO | Commerce Bank |
| $150,000–350,000 | MARTZ & WILSON LLP | SAINT LOUIS, MO | PNC Bank, National Association |
| $150,000–350,000 | MARY ELLE FASHIONS, INC | SAINT LOUIS, MO | Carrollton Bank |
| $1–2 million | MARY QUEEN AND MOTHER ASSOCIATION DBA MARY QUEEN & MOTHER CE | SAINT LOUIS, MO | Commerce Bank |
| $350,000–1 million | MARY QUEEN OF PEACE CHURCH | SAINT LOUIS, MO | Peoples National Bank, National Association |
| $150,000–350,000 | MARY R. WOLFF REAL ESTATE MANAGEMENT CO. | SAINT LOUIS, MO | The Central Trust Bank |
| $150,000–350,000 | MARY RYDER HOME | SAINT LOUIS, MO | Enterprise Bank & Trust |
| $1–2 million | MARYVILLE CONSULTING GROUP, INC | SAINT LOUIS, MO | First Bank |
| $350,000–1 million | MASK BROTHERS TRUCKING CO., INC. | SAINT LOUIS, MO | Busey Bank |
| $150,000–350,000 | MASSIE FUDEMBERG GOLDBERG LLC | SAINT LOUIS, MO | Cass Commercial Bank |
| $150,000–350,000 | MATERIAL SALES COMPANY INC | SAINT LOUIS, MO | Cass Commercial Bank |
| $150,000–350,000 | MATHENY HEATING AND COOLING SERVICE, INC. | SAINT LOUIS, MO | Enterprise Bank & Trust |
| $150,000–350,000 | MATHEWS DICKEY BOYS AND GIRLS CLUB | SAINT LOUIS, MO | Commerce Bank |
| $350,000–1 million | MATTER LLC | SAINT LOUIS, MO | UMB Bank, National Association |
| $2–5 million | MAUNE RAICHLE HARTLEY FRENCH & MUDD LLC | SAINT LOUIS, MO | First Mid Bank & Trust, National Association |
| $150,000–350,000 | MB CONSULTING GROUP, INC | SAINT LOUIS, MO | Enterprise Bank & Trust |
| $150,000–350,000 | MC HOTELS, LLC | SAINT LOUIS, MO | Sterling Bank |
| $150,000–350,000 | MCARTHUR'S SYSTEMS,INC. | SAINT LOUIS, MO | BMO Bank National Association |
| $150,000–350,000 | MCCARTHY SPICE & BLENDS COMPANY | SAINT LOUIS, MO | Simmons Bank |
| $350,000–1 million | MCCAY TOOL & ENGINEERING CO. INC. | SAINT LOUIS, MO | Itria Ventures LLC |
| $350,000–1 million | MCCAY TOOL & ENGINEERING CO., INC. | SAINT LOUIS, MO | Busey Bank |
| $150,000–350,000 | MCCORD DESIGN GROUP | SAINT LOUIS, MO | Commerce Bank |
| $2–5 million | MCCORMACK BARON SALAZAR, INC. | SAINT LOUIS, MO | Enterprise Bank & Trust |
| $1–2 million | MCGRATH & ASSOCIATES, INC. | SAINT LOUIS, MO | Montgomery Bank |
| $150,000–350,000 | MCGUIRE MOVING AND STORAGE, INC. | SAINT LOUIS, MO | Royal Banks of Missouri |
| $350,000–1 million | MCKNIGHT PLACE EXTENDED CARE, L.L.C. | SAINT LOUIS, MO | Simmons Bank |
| $350,000–1 million | MCMAHON BERGER PC | SAINT LOUIS, MO | St. Louis Bank |
| $1–2 million | MCMAHON FORD CO. INC. | SAINT LOUIS, MO | Bank of Washington |
| $150,000–350,000 | MCMAHON GROUP, INC | SAINT LOUIS, MO | Busey Bank |
| $150,000–350,000 | MCMANUS CONSTRUCTION INC. | SAINT LOUIS, MO | Heritage Community Bank |
| $150,000–350,000 | MDS MANUFACTURING, LLC | SAINT LOUIS, MO | Busey Bank |
| $1–2 million | MECHANICAL SOLUTIONS, INC. | SAINT LOUIS, MO | Southern Bank |
| $150,000–350,000 | MED SPA PARTNERS, L.L.C. | SAINT LOUIS, MO | Simmons Bank |
| $150,000–350,000 | MEDCURO MANUFACTURING LLC | SAINT LOUIS, MO | Commerce Bank |
| $150,000–350,000 | MEDI-PLEX HEALTH CARE PROFESSIONALS, L.L.C. | SAINT LOUIS, MO | Triad Bank |
| $350,000–1 million | MEDIA MANAGEMENT, INC. | SAINT LOUIS, MO | U.S. Bank, National Association |
| $350,000–1 million | MEDIACROSS, INC. | SAINT LOUIS, MO | Simmons Bank |
| $150,000–350,000 | MEDICAL EMPLOYMENT DIRECTORY OF ST LOUIS | SAINT LOUIS, MO | Cass Commercial Bank |
| $150,000–350,000 | MEDIEQUIP, INC. | SAINT LOUIS, MO | Busey Bank |
| $150,000–350,000 | MEDNIK WIPING MATERIALS COMPANY | SAINT LOUIS, MO | Midland States Bank |
| $150,000–350,000 | MEECO ACQUISITIONS LLC | SAINT LOUIS, MO | Cass Commercial Bank |
| $150,000–350,000 | MEMORY CARE HOME SOLUTIONS | SAINT LOUIS, MO | Midwest BankCentre |
| $150,000–350,000 | MERIT HOME HEALTH CARE, INC. | SAINT LOUIS, MO | Enterprise Bank & Trust |
| $150,000–350,000 | MERLIN STELZER SALES COMPANY | SAINT LOUIS, MO | Commerce Bank |
| $1–2 million | MERLO AUTOMOTIVE GROUP, INC | SAINT LOUIS, MO | Midwest BankCentre |
| $1–2 million | MERLO PLUMBING CO., INC. | SAINT LOUIS, MO | BMO Bank National Association |
| $2–5 million | METAL EXCHANGE CORPORATION | SAINT LOUIS, MO | BMO Bank National Association |
| $150,000–350,000 | METAL FABRICATORS OF ST. LOUIS, LLC | SAINT LOUIS, MO | Triad Bank |
| $150,000–350,000 | METALTECH INC | SAINT LOUIS, MO | Cass Commercial Bank |
| $150,000–350,000 | METAPHASE DESIGN GROUP, INC | SAINT LOUIS, MO | The Central Trust Bank |
| $150,000–350,000 | METRO COMMERCIAL SWEEPING, LLC | SAINT LOUIS, MO | Newtek Small Business Finance, Inc. |
| $150,000–350,000 | METROPOLITAN FIRE PROTECTION SYSTEM, L.L | SAINT LOUIS, MO | U.S. Bank, National Association |
| $150,000–350,000 | MHI HOLDINGS LLC | SAINT LOUIS, MO | The Bank of Houston |
| $150,000–350,000 | MHOONDRIED INC | SAINT LOUIS, MO | Bank of America, National Association |
| $2–5 million | MHS LEGACY GROUP, INC. | SAINT LOUIS, MO | Busey Bank |
| $150,000–350,000 | MICHAEL GENOVES DIAMOND AND ESTATE BROKER, INC. | SAINT LOUIS, MO | Triad Bank |
| $150,000–350,000 | MICHAEL P TRAVIS DDS LLC | SAINT LOUIS, MO | UMB Bank, National Association |
| $150,000–350,000 | MICHAEL REHME | SAINT LOUIS, MO | U.S. Bank, National Association |
| $150,000–350,000 | MICHAEL W. NOBLE, DMD, PC | SAINT LOUIS, MO | Arsenal CU |
| $350,000–1 million | MICKES O'TOOLE LLC | SAINT LOUIS, MO | Great Southern Bank |
| $350,000–1 million | MICROFINISH CO., INC. | SAINT LOUIS, MO | The Missouri Bank |
| $350,000–1 million | MICROFINISH IPC LLC | SAINT LOUIS, MO | The Missouri Bank |
| $150,000–350,000 | MID AMERICA PACKAGING, INC. | SAINT LOUIS, MO | First Bank |
| $150,000–350,000 | MID AMERICA REGIONAL INFORMATION SYSTEMS, INC | SAINT LOUIS, MO | Commerce Bank |
| $2–5 million | MID-AMERICA TRANSPLANT SERVICES | SAINT LOUIS, MO | BMO Bank National Association |